1.1. Contact organisation
[PT1] Statistics Portugal
1.2. Contact organisation unit
Unit: Statistics Portugal, Demographic and Social Statistics Department, Living Conditions Statistics Unit.
1.3. Contact name
Confidential because of GDPR
1.4. Contact person function
Confidential because of GDPR
1.5. Contact mail address
Avenida António José de Almeida, 5 - 1000-043 Lisboa
1.6. Contact email address
Confidential because of GDPR
1.7. Contact phone number
Confidential because of GDPR
1.8. Contact fax number
Confidential because of GDPR
2.1. Metadata last certified
5 January 2026
2.2. Metadata last posted
5 January 2026
2.3. Metadata last update
5 January 2026
3.1. Data description
The Survey on the Use of Information and Communication Technologies by Families is an annual survey conducted since 2002. In Portugal, it has been conducted since 2002.
In 2025, the survey collects data on the access to information and communication technologies (ICT), on the use of the internet, e-government use of electronic (eID) and e-commerce as well as e-skills and privacy and protection of personal data.
3.1.1. Survey name in national and English languages
National language: Inquérito à Utilização de Tecnologias de Informação e da Comunicação pelas Famílias 2025
English: Survey on the Use of Information and Communication Technologies by Families 2025
Questionnaire(s) in national language(s) and the translation in English are available in the Annexes below.
3.2. Classification system
The following common concepts and definitions apply under the Integrated European Social Statistics (IESS):
- the International Standard Classification of Education (ISCED) 2011 published in the following breakdowns: low (ISCED levels 0-2: no formal education, primary education or lower secondary education), medium (ISCED levels 3-4: upper secondary or post-secondary non-tertiary education) and high (ISCED levels 5-6: tertiary programmes which normally need a successful completion of ISCED 3 or 4, or second-stage tertiary education leading to an advanced research qualification);
- the International Standard Classification for Occupation ISCO-08 at the 2-digit level;
- the Classification of Economic Activities (NACE Rev.2-2008), at section level;
- the Common classification of territorial units for statistics (NUTS 1) – finer granularity of NUTS 2 is provided on optional basis by some Member States;
- the SCL – Geographical code list;
- information about household income is provided at lower level of detail.
Additional classifications used in the national questionnaire:
- NUTS2
- ISO 3166-1 - international standard - codes for the representation of country names (Iso alpha2)
3.3. Coverage - sector
The ICT survey in households and by individuals covers those households having at least one member in the age group 16 to 74 years old. Individuals aged 75 to 89 are covered by some countries on voluntary basis.
Internet access of households refers to the percentage of households that have an internet access, so that anyone in the household could use the internet.
3.3.1. Differences in scope at national level
No differences from the main Eurostat scope.
3.4. Statistical concepts and definitions
The survey is collecting data of internet users, individuals who have used the internet in the three months prior to the survey.
This annual survey is used to benchmark ICT-driven developments, both by following developments for core variables over time and by looking in greater depth at other aspects at a specific point in time. While the survey initially concentrated on access and connectivity issues, its scope has subsequently been extended to cover a variety of subjects (for example, the use of internet, e-government, use of eID, e-commerce, e-skills and privacy and protection of personal data) and socio-economic analysis (such as regional diversity, gender specificity, differences in age, education and the employment situation). The scope of the survey with respect to different technologies is also adapted to cover new product groups and means of delivering communication technologies to end-users.
For more details on the methodology applicable in each survey year, please consult the Compiler's Manual for the respective year.
Deviations from standard ICT concepts: Not applicable.
3.5. Statistical unit
Households and Individuals
3.6. Statistical population
In the ICT usage survey, the target population for the different statistical units is:
- individuals: all individuals aged 16 to 74; optionally 75-to 89.
- households: all (private) households with at least one member aged 16 to 74; optionally with at least one member aged 75 to 89, but no member aged 16 to 74.
Target population composed of households and/or individuals:
- Number of households with at least one member aged 16-74: 3,918,797
- Number of individuals aged 16-74: 8,008,323
- Number of households with at least one member aged 75 to 89, but no member aged 16 to 74: Not applicable.
- Number of individuals aged 75-89: Not applicable.
3.6.1. Non-compulsory age groups
Non-compulsory age groups also included in the target population:
| No | Yes | Age scope | |
|---|---|---|---|
| Individuals younger than 16? | x | ||
| Individuals aged 75-89? | x | ||
| Individuals older than 89? | x |
3.6.2. Population not covered by the data collection
| Non-target population (the difference between the total population and the target population) |
Households | Individuals |
|---|---|---|
| Approximate number of units outside the mandatory scope of the survey (for example individuals younger than 16 or older than 74; households with all members over 74 years old). | 612,253 | 2,757,404 |
| Approximate number of units outside the age scope 16 to 89, if the optional age scope 75 to 89 is included. |
Not included | Not included |
| Estimate of the resulting percentage of under-coverage (non-covered population compared to the total country), if applicable | 13.5% | 25.6% |
3.7. Reference area
All national territory is covered (mainland, Região Autónoma dos Açores and Região Autónoma da Madeira); no parts excluded.
3.8. Coverage - Time
Year 2025
3.9. Base period
Not applicable
Percentages of ‘Households’ and Percentages of ‘Individuals’
For most questions the reference period is the last three months before the interview. Questions in the modules on e-government and eID refer to the 'last year' prior to the interview.
Deviation from this statement: In general, the reference period for the ICT variables correspond to the 3 months prior to the date of the interview (it covers a period that depends on the data collection period, that started on 15 May and ended 11 August 2025); there are however specific variables where “previous twelve months” are specified in accordance to the EU model questionnaire.
The reference period for the socio-demographic background variables is the date of the interview.
5.1. Survey period
Data collection took place from 15 May to 11 August 2025.
6.1. Institutional Mandate - legal acts and other agreements
The legal basis for the 2025 EU survey on the use of ICT in households and by individuals is the Regulation (EU) 2019/1700 of the European Parliament and of the Council of 10 October 2019 establishing a common framework for European statistics relating to persons and households, based on data at individual level collected from samples (OJ L 261 I, 14 October 2019, p. 1), as implemented by the Commission Implementing Regulation (EU) 2024/2182 of 2 September 2024 specifying the technical items of the data set, establishing the technical formats for transmission of information and specifying the detailed arrangements and content of the quality reports on the organisation of a sample survey in the use of information and communication technologies domain for reference year 2025 in accordance with Regulation (EU) 2019/1700 of the European Parliament and of the Council (OJ L - 2024/2182, 3 September 2024) and Commission Delegated Regulation (EU) 2024/2515 of 9 July 2024 supplementing Regulation (EU) 2019/1700 of the European Parliament and of the Council by specifying the number and titles of the variables for the use of information and communication technologies statistics domain for the reference year 2025 (OJ L, 2024/2515, 26 September 2024).
Complementary national legislation constituting the legal basis for the survey on the use of ICT in households and by individuals: This survey is included in the National Statistics System and it is mandatory (Law no. 22/2008, of 13 May).
6.2. Institutional Mandate - data sharing
Data is not available to other NSS agencies besides Statistics Portugal. Inside Statistics Portugal, data collected are available for the internal units inside Statistics Portugal ensuring validation, weighting and estimation of final results and standard errors, via a platform (Infoview BusinessObjects 3.0) were consultations and analyses can be done.
7.1. Confidentiality - policy
The collection, processing and dissemination of data is carried out in accordance with the provisions of the National Statistical System Law (Law 22/2008 of 13 May), namely Article 6 which establishes the application of the principle of statistical confidentiality of data.
Any statistical unit, directly or indirectly identifiable, cannot be disclosed, not only for the protection granted by this principle, but also for the rules arising from the application of the General Data Protection Regulation.
The breach of statistical confidentiality is punishable not only disciplinary, but also criminally, according to Article 32 of the National Statistical System Law.
7.2. Confidentiality - data treatment
The treatment of statistical confidentiality (according to Law 22/2008 of May 13, and also ensured by Eurostat under regulation No. 1000/2007, of 29 August) consists of the suppression of individual identification, of the variables used in the selection of the sample and of those associated with field work, in addition to the use top/bottom coding and grouping in several variables, to minimize the risk of identification with a view to obtaining a file for scientific purposes.
8.1. Release calendar
A calendar for press releases is available on Statistics Portugal Website.
8.2. Release calendar access
The press release calendar is available on Statistics Portugal website, at the following website.
8.3. Release policy - user access
The following principles are included in the Statistics Portugal general policy for release of the data to users, and are followed by ICT use survey in households and by individuals:
- Provide the official statistical information at cost free in the Official Statistics Portal;
- Provide objective, timely and punctual official statistical information, accompanied by the respective statistical metadata and, eventually, other information that facilitates its interpretation;
- The official statistical information should be impartial and released simultaneously to all users;
- Provide official statistical information on pre-announced calendar established based on exclusively technical-regulatory criteria and having in consideration of the quality/up-to-date commitment;
- Publicize the changes as far in advance as possible to the dissemination calendar and its justification, maintaining the home calendar accessible.
Annual
10.1. Dissemination format - News release
A press release is published every year in the end of November with the results of the latest survey on ICT Usage in households and by individuals.
The press releases, both in Portuguese and in English, are available at Statistics Portugal website under the theme Research and Development, in the following link: Information and knowledge society - household survey 2025.
10.2. Dissemination format - Publications
The results of the national Survey on ICT Usage in Households are not published in a Publication format.
10.3. Dissemination format - online database
The aggregated results of the survey are available in a Database at Statistics Portugal website, under the theme Research and Development, sub theme Information Society, in the following link.
10.3.1. Data tables - consultations
Not available.
10.4. Dissemination format - microdata access
According to Article 6 of the National Statistical System Law (Law 22/2008 of 13 May), individual statistical data on natural and legal persons may only be provided for scientific purposes in an anonymized form, to accredited researchers.
The accreditation of researchers is done by the General Directorate of Education and Science Statistics.
10.5. Dissemination format - other
The main ICT use survey in households and by individuals results are included in two multi-theme annual publications of Statistics Portugal: the Statistical Yearbook and the Annual Report on the Sustainable Development Goals Indicators (SDG) for Portugal.
10.5.1. Metadata - consultations
Not available.
10.6. Documentation on methodology
The main methodological aspects of the ICT use survey in households and by individuals are described in a methodological document, which is mandatory for all surveys carried out in the context of the National Statistical System.
All methodological documents are freely accessed on the Internet, at Statistics Portugal website, complying with the principles defined in the “European Statistics Code of Practice”.
10.6.1. Metadata completeness - rate
The methodological document intends to be as complete as possible, including all the necessary information about the scope, sample, data collection, grossing up procedures, concepts, classifications and indicators available on Statistics Portugal Website. It also includes the national questionnaire and information about users of the data, the contact persons of the survey, the dissemination products, the schedule of dissemination, legislation, etc.
10.7. Quality management - documentation
The European Statistics Code of Practice, a self-regulatory instrument whose main purpose is to improve trust and confidence in official statistics produced and disseminated by the statistical authorities of Member States, Candidate Countries, EFTA Members and Eurostat, reinforcing their independence, integrity and responsibility and to enhance the quality of European Statistics. (European Statistics Code of Practice).
Information Security Management System (ISMS), aligned with the best international practices, namely NP ISO / IEC 27001: 2013, is comprised of a set of policies and procedures that are now available to all Statistics Portugal’s procedures, and which allow the operationalization of the System. (Information Security Management System)
The following are noteworthy strategic documents to Statistics Portugal and made available in its Portal:
- The 2019 edition of the Quality Chart (only in PT version), which formalizes Statistics Portugal’s assumed public commitment in relation to the quality and credibility of the official statistics it produces and disseminates, to the public service it provides to the society – making it clear to all information providers, users of statistical information and to the public in general – also expressing the commitment towards information security;
- The Information Security Policy (only in PT version), which sets the general principles by which Statistics Portugal carries its mission, to the assets it manages within the scope of the ISMS, following all requirements within NP ISO/IEC 27001:2013, the applicable legislation, regulation and recommendations of the ESS (European Statistical System) and EUROSTAT in what specifically concerns information security;
- The Statistical Confidentiality Policy (only in PT version), which replaces the former Statistics Portugal´s Confidentiality Chart and is part of the ISMS and formalizes the public commitment of compliance with the Principle of Statistical Secrecy assumed by Statistics Portugal as the central body responsible for the coordination and development of the national statistical activity;
- The Personal Data and Privacy Protection Policy (only in PT version), which aims to supply the providers of data information about the nature of the collected data, its intended purpose and how the data are treated.
The Dissemination policy of Statistics Portugal lays down the fundamental principles governing the dissemination of official statistics, directly or indirectly produced under its responsibility. It should have as main reference the applicable principles of the National Statistical System: technical independence, statistical confidentiality, quality and accessibility (Dissemination policy)
11.1. Quality assurance
To ensure process and data quality several procedures are carried out:
- The questionnaire and the methodological document follow a procedure of approval within the National Statistical System. This procedure is supervised by a coordination team, and implies the consultation of the questionnaire and methodological document by all departments, where opinions and recommendations are collected and adopted, if relevant.
- Data collection is carried out by interviewers (face to face or telephone interviews) or via a web platform, using specific computer programs backed up with validation rules (for guarantying answers quality, coherence between related questions and the observance of the routing), instructions for the interviewers/respondents and with explanations about the technologies which are eventually more difficult to be understood by respondents.
- Interviewers follow a training action before the beginning of data collection, backed up with support documentation, information about the necessary procedures to be taken and rules about what should be considered in each question, always following Eurostat recommendations.
- During the data collection, the interviewers work and the response rate are periodically supervised, the latest according to previously defined goals.
- Before sending the database to be grossed-up by the Department of Methodology and Information Systems, the data is submitted to validation procedures both by the Department of Data Collection and Management and the Department of Demographic and Social Statistics, where therefore, confirmations with team-work, (re)codifications and corrections can be made to the collected data.
11.2. Quality management - assessment
Despite the efforts made by the data collection team, in 2025 the response rate remained low compared to 2019 (56.9% in 2025 compared to 71.0% in 2019), although higher than the response rates obtained during the pandemic (2020 to 2022) and slightly lower than the response rates obtained in 2023 (60,0%) and 2024 (60,7%).
12.1. Relevance - User Needs
The main users of Survey on ICT Usage in households and by individuals are:
1. Internal users (of the National Statistical System):
- Statistics Portugal - National Accounts Department
- Regional Directorates of Statistics of Região Autónoma dos Açores (SREA) and Região Autónoma da Madeira (DREM) that act as delegations of Statistics Portugal for regional data collection purposes;
- Directorate-General of Education and Science Statistics of the Ministry of Education and the Ministry of Science, Technology and Higher Education
- Bank of Portugal
2. Other users:
- ANACOM - National Authority of Communications
- OberCom - Communication Observatory
- Eurostat
- OECD
- ITU
12.2. Relevance - User Satisfaction
Statistics Portugal Dissemination Policy foresees a regular monitoring and assessment of the quality and accessibility of disseminated data, in order to ensure continued improvement of dissemination activity.
This process involves:
- The different type of users are regularly surveyed on their satisfaction regarding products and services made available to them by Statistics Portugal;
- User comments, suggestions and complaints are viewed as real opportunities to further improve the dissemination activity of Statistics Portugal;
- User comments, suggestions and complaints are duly treated in accordance with the procedures established in Statistics Portugal's Quality Charter;
- User comments, suggestions and complaints, where relevant, leads to the adoption of measures to further improve the activity of Statistics Portugal, particularly in the dissemination function.
12.3. Completeness
All variables required are included in the microdata.
12.3.1. Data completeness - rate
100%. All variables required are included in the microdata.
13.1. Accuracy - overall
Random errors are essentially caused by the respondents and by the records of the interviewers. As for systematic errors, they are caused by the non-responses of some households, which are compensated in the final weights which integrates a factor of non-responses and calibration, and are described below.
13.2. Sampling error
The unit non-response is dealt by means of a non-response factor (ratio between the total of households and the sum of the respondent households’ design weights) which is included in the calculation of final weights.
The weight is calculated in three steps:
- 1st step: determination of the design weight, which incorporates the survey design information and is given by the inverse probability of selection of each statistical unit (based on the Horvitz-Thompson estimator);
- 2nd step: application of a non-response adjustment factor to the weight calculated in first step;
- 3rd step: adjustment of the weight obtained in step 2, applying a calibration procedure to ensure that the distributions of households and individuals are consistent with the structure of the correspondent known populations. For households, the auxiliary information (margins) is the totals of households by NUTS2 - 2024 Version (sourced from national LFS). For individuals, the margins are the total of individuals by NUTS2 (2024 Version), sex and age group (sourced from the Annual estimates of resident population).
The sampling design includes a longitudinal component by means of a rotating panel in which ¼ of the sample rotates each year.
For the calculation of the estimate’s variance a Jackknife estimator was used. This technique supposes the partition of the sample into groups and the calculation of estimates for the all sample and for the obtained sub samples, by systematically leaving out each one of the constituted groups to the global sample and then finding the average of these calculations. The variance is estimated using the variability between the estimates obtained by the given sub samples and the one calculated using the all sample.
The standard error was calculated using the precision of an estimate calculated by the correspondent Coefficient of Variation.
These calculations are performed using the R package survey (by Thomas Lumley - The Comprehensive R Archive Network (r-project.org)).
13.2.1. Sampling error - indicators
Precision estimates for the question "Individuals having ordered goods or services for private use over the internet in the last 12 months" (individuals who ticked 'Within the last 3 months' or 'Between 3 months and a year ago' in in the question “When did you last buy or order goods or services for private use over the internet?”):
- Number of respondents (absolute value for ‘Yes’ answers): 4,317
- Estimated proportion (in %): 60.5%
- Standard error (in percentage points): 0.65
Details of the breakdowns are available in document INFOSOC_HHNSI_A_2025 in the Annexes below.
13.3. Non-sampling error
See more details on non-sampling error below.
13.3.1. Coverage error
Exclusion of the people living in collective dwellings as well as homelessness people which represent approximately 1% of the target population.
The update is continuous based only on the information from fieldwork (from other surveys), just very recently started the update with the use of administrative data.
13.3.1.1. Over-coverage - rate
From the 16,391 sample dwellings, at about 14,7% are dwellings not classified as main residence or where there are no individuals aged 16 to 74 years old.
13.3.1.2. Common units - proportion
Not requested in the ICT survey.
13.3.2. Measurement error
- Measurement errors: No errors were detected.
However it could occur typing errors, not possible to detected with the coherence validation rules implemented in the data collection computer program. And it could occur errors related to misinterpretation or misunderstanding of some question or instruction. - Questionnaire design and testing: The first version of the questionnaire is developed by Demographic and Social Statistics Unit (translation of the Eurostat Model Questionnaire and adaptation to national reality) including the relevant instructions to respondents. This version is discussed with the Data Collection Unit, resulting in a second version.
This second version, together with the methodological document, is object of a compulsory procedure of approval and register within the National Statistical System. This procedure is supervised by a coordination team, and implies the consultation of the questionnaire and methodological document by all departments, where opinions and recommendations are collected and adopted, if relevant. - Interviewer training: Face-to-face and telephone interviews were made by external interviewers, already selected for other household surveys.
Interviewers followed a training action before the begin of data collection, backed up with support documentation, information about the necessary procedures to be taken and rules about what should be considered in each question, always following Eurostat recommendations.
The interviews are computer assisted backed up with validation rules (for guarantying answers quality, coherence between related questions and the observance of the routes), instructions for the interviewers/respondents and with explanations about the technologies which are eventually more difficult to be understood by respondents. - Proxy interview rates: Proxy interview are not allowed in this survey.
13.3.3. Non response error
Information about non-respondents: Not available.
13.3.3.1. Unit non-response - rate
The unit non-response rate is the ratio of the number of in-scope non-respondents (= number of rejected interviews) to the number of eligible elements selected from the sampling frame.
Unit non-response rate for
- Households with at least one member aged 16 to 74 : 43.1%
- Households with at least one member aged 75 to 89, but no member aged 16 to 74: Not included
- Individuals (aged 16-74): 43.1%
- Individuals (aged 75-89): Not included
13.3.3.1.1. Unit non-response – sample sizes
| Number of households with at least one member aged 16-74 | Number of households with at least one member aged 75-89, but no member aged 16-74 | Number of individuals aged 16-74 |
Number of individuals aged 75-89 | Number of individuals (< 16) |
Number of individuals (> 89) |
|
|---|---|---|---|---|---|---|
| Gross sample [A] The number of households/individuals initially selected from the sampling frame (if not applicable, indicate why below the table) |
16,391 | 16,391 | ||||
| Ineligible: out-of-scope [B] For example, when a selected household is not in the target population because all members are over 75 years old or when no dwelling exists at the selected address, or a selected individual has died between the reference data of the sampling frame at the moment of the interview. |
1,862 | 1,862 | ||||
| Number of eligible elements [C] Gross sample size corrected of the ineligible cases |
14,529 | 14,529 |
||||
| Net sample size or final sample [D] The net sample size (or final sample) corresponds to the number of households/individuals that can be used in the final database. |
8,261 | 8,261 | ||||
| Unit response rate [E] = [D] / [C] The unit response rate is the ratio of the number of in-scope respondents (= the number of achieved interviews or the net sample size) to the number of eligible elements selected from the sampling frame. |
56.9% | 56.9% |
Comments, if any:
13.3.3.1.2. Unit non-response – methods, minimization and substitution
- Methods used for dealing with unit non-response:
Measures taken to reduce the unit non-response:
-
- Previous notification in the form of a letter (or e-mail) sent to all dwellings sampled;
- Introduction of self-administered internet interviews to all dwellings in the first phase of data collection and possibility to answer via CAWI during the entire period of data collection, allowing flexibility in the time of response;
- For CAPI and CATI the individuals had the possibility to schedule the telephone interview (choosing day and hour of convenience);
- To minimise the number of refusals, supervisors received instructions to insist with individuals through a systematic plan of insistences where respondents were informed about the main purposes of the data collection and the importance of their contribution.
- Methods used for minimizing unit non-response: The design weight of each unit (dwellings and individuals), i.e. the inverse of the probability of selection, is multiplied by a factor of non-response.
- Substitution permitted: Not applicable; substitutions and proxy interviews are not allowed.
- Substitution rate (in %): Not applicable.
13.3.3.2. Item non-response - rate
Items with low response rates (observed rates in %): Not applicable. The computer program do not allow blank answers; "don't know" and/or "refusal" are options foreseen for some questions.
13.3.4. Processing error
For the variables Occupation in main employment and Sector in employment, a description is collected and later codified according ISCO and NACE (both at 2 digit). Sometimes the descriptions are insufficient to codify correctly and these records are treated as non-response and considered to imputation procedure as described in item 18.5.2.
13.3.5. Model assumption error
Not applicable
14.1. Timeliness
Date of data dissemination at national level:
At national level, data is disseminated (in press release format and database indicators on Statistics Portugal website) in the end of November of year n, with n being the year of data collection.
A delay in the release never happened, even during the COVID-19 pandemic when response rates decreased sharply.
14.1.1. Time lag - first result
Restricted from publication
14.1.2. Time lag - final result
Restricted from publication
14.2. Punctuality
The final microdata file was sent two days before the target date (5 October) and according to Eurostat standards and transmission rules.
14.2.1. Punctuality - delivery and publication
The final microdata file was sent two days before the target date (5 October) and according to Eurostat standards and transmission rules.
15.1. Comparability - geographical
There is no problem of comparability across the country’s regions.
15.1.1. Asymmetry for mirror flow statistics - coefficient
Not relevant
15.2. Comparability - over time
Possible limitations in the use of data for comparisons over time:
In 2024 there was a sample resizing to ensure compliance with the new version of NUTS (NUTS-2024), maintaining representativeness for all NUTS 2 regions, and the new sample size will be applied gradually over the next 4 years (from 2024 to 2027).
However, this change is not enough to warrant the designation of a break in series in the 4 years in which the sample size will be applied.
15.2.1. Length of comparable time series
The length of comparable time series depends on the module and variable considered within each of the modules of the survey.
15.3. Coherence - cross domain
Not applicable
15.3.1. Coherence - sub annual and annual statistics
Not applicable
15.3.2. Coherence - National Accounts
Not applicable
15.4. Coherence - internal
All statistics are coherent within the dataset provided by the country.
15.4.1. Survey questionnaire – mandatory questions
MANDATORY questions in the Eurostat model questionnaire 2025: Table 15.4.1. of document INFOSOC_HHNSI_A_2025 in the Annexes lists the questions for which the coverage of subjects and characteristics reflected in the national questionnaire differs from Annex 2 of the Commission Delegated Regulation (EU) 2024/2515 of 9 July 2024.
15.4.2. Survey questionnaire – optional questions
Adoption of OPTIONAL questions and items in the Eurostat model questionnaire 2025: Table 15.4.2. of document INFOSOC_HHNSI_A_2025 in the Annexes lists the optional questions from the annual Eurostat model questionnaire 2025 included in the national questionnaire and their coverage for age groups beyond the standard scope.
15.4.3. Survey questionnaire – additional questions at national level
Additional questions introduced in the national questionnaire in 2025: Details of the questions are in document INFOSOC_HHNSI_A_2025 available in the Annexes below.
15.4.4. Survey questionnaire – deviations
Effects of deviations from the routing used in the Eurostat model questionnaire: All statistics are coherent within the dataset.
Restricted from publication
17.1. Data revision - policy
Statistics Portugal has a revision policy document that seeks to clarify the key factors of a revision, the typology of revision that may occur and the dimensions governing a revision’s analysis. It also explains the General and Operational Principles of the revisions policy that Statistics Portugal will consolidate in the future (Revisions policy).
17.2. Data revision - practice
Not foreseen.
17.2.1. Data revision - average size
Not relevant
18.1. Source data
The source of the raw data is described with more details in the paragraphs below.
18.1.1. Sampling frame
This survey is a stand-alone survey (since 2003) and is included in the National Statistics System and it is mandatory (Law no. 22/2008, of 13 May).
In 2024, a new sampling frame was selected from the National Dwellings Register (NDR) which in turn uses information collected in the 2021 Census. The geographical coverage refers to the total territory. It is made up of all the addresses of private dwellings of usual residence and excludes collective households and institutions (approximately 1% of total population). Its size is approximately 1.5 million dwellings of usual residence.
The sampling frame was stratified in one-stage cluster samples. In each stratum (NUTS 3– 2024 version) the clusters were selected systematically with probability proportional to size (number of private dwellings of usual residence). The clusters were constituted by one or more contiguous grid INSPIRE cells with 1 Km2 of area. A total of 655 clusters, or PSU, were selected.
From the year 2024 to the year 2026 two sampling frames will coexist. Both sampling designs are similar.
There are no known shortcomings.
18.1.2. Sampling design
Sampling design includes a sample of dwellings (each of which corresponding to a Secondary Sampling Unit) selected systematically. In each selected dwelling, one person aged 16 to 74 is selected by the last birthday method.
The sampling design includes a longitudinal component by means of a rotating panel in which ¼ of the sample rotates each year. The transition between the two sampling frames was established to occur between 2024 and 2026: each year, a new rotation (1/4) is drawn from the new sampling frame. In 2027 all four rotations of the sample will belong to the new sampling frame.
The sampling size has increased to 4,718 in each rotation, with the purpose to give answer to the national criterium for NUTS 2 – 2024 version, so after the transition period, the national sample size will contain 18,872 dwellings.
According to information collected in previous years, dwellings that are in one of the following situations were not followed in 2025:
- out-of-scope, i.e. not occupied (vacant, secondary use, business, etc.);
- only including ineligible individuals (younger and/or older than 16 to 74 years old) in two consecutive years;
- that have refused to answer the survey in two consecutive years or;
- when the selected individual has a severe disability or health condition preventing him/her to answer the questionnaire in two consecutive years.
Therefore, and according to the sample of the previous year, the sample size collected in 2025 comprised 16,391 dwellings.
18.1.3. Net effective sample size
Restricted from publication
18.2. Frequency of data collection
Annual
18.3. Data collection
- Methods used to gather data: CAPI, CATI and CAWI
- Short description of the survey method: The 2025 ICT survey uses a mixed-mode data collection of face-to-face interviews (CAPI), telephone interviews (CATI) and self-administered internet interviews (CAWI).
No subsamples were selected for the different modes of data collection. Instead, a 2-step approach has been implemented:
-
- all 16,391 dwellings selected for the 2025 gross sample were initially offered the possibility to fulfil a self-administered internet questionnaire (CAWI);
- after a predefined period were the collection is made available only via CAWI, the dwellings that have not answered the questionnaire, are moved to CATI or CAPI data collection mode, depending on the availability of telephone on the sample and of the respondent preference for answering.
The three methods are available based on optimization of response rates and respondents' preference; individuals have the possibility to answer via CAWI during the entire period of data collection.
Regarding the number of interviews completed for individuals aged between 16 to 74 years (8,261), 20.4% (1,689) were face-to-face interviews, 33.1% (2,732) were telephone interviews and 46.5% (3,840) were web interviews.
The interviews have been made in households with at least one individual aged 16 to 74 years old. After listing all the eligible individuals in each unit, the method of last birthday (with reference to date of first interview) has been used to select the respondent: one individual aged between 16 to 74 years, if any.
- Variables completed from an external source:
For Household income (equivalised) in quintiles, the information was collected in euro currency, in large size bands and in exact value.
The size bands used in data collection were defined in accordance to the EU-SILC more recent data (EU-SILC 2024), and in order to enable quartile and quintile calculations. The EU-SILC 2024 data was also used as reference to calculate an estimated value for each answer in size band.
18.4. Data validation
Data collection was carried out by interviewers (face-to-face and telephone) or via a web platform, using specific computer programs backed up with validation rules (for guarantying answers quality, coherence between related questions and the observance of the routes), instructions for the interviewers/respondents and with explanations about the technologies which are eventually more difficult to be understood by respondents.
Before sending the database to be grossed-up by the Department of Methodology and Information Systems, the data have been submitted to validation procedures both by the Department of Data Collection and Management and the Department of Demographic and Social Statistics, where therefore, confirmations with team-work, (re)codifications and corrections can be made to the collected data.
18.5. Data compilation
Imputation was used in case of non-response or refusal to answer to: activity status, sector in employment, occupation in employment, education attainment level and household income (including the imputation of invalid/too low income values declared by the respondents).
The average household income declared by individuals with similar characteristics (in terms of education level, age class and activity status) was used to impute the household income missing or invalid data.
For the other variables, missing data were imputed using data previously collected for individuals has been interviewed in previous years (the latest year for activity status); if the individual have not been interviewed in previous years, the modal value declared by individuals with similar characteristics has been used.
18.5.1. Imputation - rate
For the target indicator "Individuals having ordered goods or services for private use over the internet in the last 12 months" (individuals who ticked 'Within the last 3 months' or 'Between 3 months and a year ago' in the question “When did you last buy or order goods or services for private use over the internet?”:
- Imputation rate (% of observations): No imputation was made.
- Imputation rate (share of estimate): No imputation was made.
18.5.2. Use of imputation methods
Methods used to impute item non-response:
- Imputation was used in case of non-response or refusal to answer to: employment situation, sector in employment, occupation in employment, education attainment level and to household income; for the latest, imputation was also considered when invalid (too low) income was declared.
- For the household income the average household income declared by individuals with similar characteristics (in terms of education level, age class and employment situation) was used for imputation.
- For the remaining variables it was used for imputation, the information collected in years before (the latest year for the employment situation); if the individual have not been interviewed in years before, the modal value declared by individuals with similar characteristics was used.
18.5.3. Grossing-up procedures
Grossing up procedures have been applied to Individuals and/or Households: Individuals and Households
Description of the weighting procedures:
The weight is calculated in three steps:
- 1st step: determination of the design weight, which incorporates the survey design information and is given by the inverse probability of selection of each statistical unit;
- 2nd step: application of a non-response adjustment factor to the weight calculated in first step;
- 3rd step: adjustment of the weight obtained in step, applying a calibration procedure to ensure that the distributions of households and individuals are consistent with the structure of the correspondent known populations. For households, the auxiliary information (margins) is the totals of households by NUTS 2 - 2024 version (sourced from national LFS). For individuals, the margins are the total of individuals by NUTS 2 (2024 version), sex and age group (sourced from the Annual estimates of resident population).
18.6. Adjustment
Not relevant
18.6.1. Seasonal adjustment
Not relevant
No comments.
The Survey on the Use of Information and Communication Technologies by Families is an annual survey conducted since 2002. In Portugal, it has been conducted since 2002.
In 2025, the survey collects data on the access to information and communication technologies (ICT), on the use of the internet, e-government use of electronic (eID) and e-commerce as well as e-skills and privacy and protection of personal data.
5 January 2026
The survey is collecting data of internet users, individuals who have used the internet in the three months prior to the survey.
This annual survey is used to benchmark ICT-driven developments, both by following developments for core variables over time and by looking in greater depth at other aspects at a specific point in time. While the survey initially concentrated on access and connectivity issues, its scope has subsequently been extended to cover a variety of subjects (for example, the use of internet, e-government, use of eID, e-commerce, e-skills and privacy and protection of personal data) and socio-economic analysis (such as regional diversity, gender specificity, differences in age, education and the employment situation). The scope of the survey with respect to different technologies is also adapted to cover new product groups and means of delivering communication technologies to end-users.
For more details on the methodology applicable in each survey year, please consult the Compiler's Manual for the respective year.
Deviations from standard ICT concepts: Not applicable.
Households and Individuals
In the ICT usage survey, the target population for the different statistical units is:
- individuals: all individuals aged 16 to 74; optionally 75-to 89.
- households: all (private) households with at least one member aged 16 to 74; optionally with at least one member aged 75 to 89, but no member aged 16 to 74.
Target population composed of households and/or individuals:
- Number of households with at least one member aged 16-74: 3,918,797
- Number of individuals aged 16-74: 8,008,323
- Number of households with at least one member aged 75 to 89, but no member aged 16 to 74: Not applicable.
- Number of individuals aged 75-89: Not applicable.
All national territory is covered (mainland, Região Autónoma dos Açores and Região Autónoma da Madeira); no parts excluded.
For most questions the reference period is the last three months before the interview. Questions in the modules on e-government and eID refer to the 'last year' prior to the interview.
Deviation from this statement: In general, the reference period for the ICT variables correspond to the 3 months prior to the date of the interview (it covers a period that depends on the data collection period, that started on 15 May and ended 11 August 2025); there are however specific variables where “previous twelve months” are specified in accordance to the EU model questionnaire.
The reference period for the socio-demographic background variables is the date of the interview.
Random errors are essentially caused by the respondents and by the records of the interviewers. As for systematic errors, they are caused by the non-responses of some households, which are compensated in the final weights which integrates a factor of non-responses and calibration, and are described below.
Percentages of ‘Households’ and Percentages of ‘Individuals’
Imputation was used in case of non-response or refusal to answer to: activity status, sector in employment, occupation in employment, education attainment level and household income (including the imputation of invalid/too low income values declared by the respondents).
The average household income declared by individuals with similar characteristics (in terms of education level, age class and activity status) was used to impute the household income missing or invalid data.
For the other variables, missing data were imputed using data previously collected for individuals has been interviewed in previous years (the latest year for activity status); if the individual have not been interviewed in previous years, the modal value declared by individuals with similar characteristics has been used.
The source of the raw data is described with more details in the paragraphs below.
Annual
Date of data dissemination at national level:
At national level, data is disseminated (in press release format and database indicators on Statistics Portugal website) in the end of November of year n, with n being the year of data collection.
A delay in the release never happened, even during the COVID-19 pandemic when response rates decreased sharply.
There is no problem of comparability across the country’s regions.
Possible limitations in the use of data for comparisons over time:
In 2024 there was a sample resizing to ensure compliance with the new version of NUTS (NUTS-2024), maintaining representativeness for all NUTS 2 regions, and the new sample size will be applied gradually over the next 4 years (from 2024 to 2027).
However, this change is not enough to warrant the designation of a break in series in the 4 years in which the sample size will be applied.
