The Survey of Household Finances (Encuesta Financiera de las Familias – EFF) is a large-scale survey conducted by the Banco de España since 2002, with the aim of providing a detailed description of the economic and financial situation of households in Spain. The survey is a key input for the analysis of the Spanish economy and for the preparation of reports and evidence to support public policy design.
The EFF provides detailed information on households’ income, assets, debts and spending, as well as on employment status, insurance products, pension plans and other relevant characteristics of households’ economic circumstances. This information makes it possible to characterise households’ financial positions and to analyse their evolution over time.
The main value of the EFF lies in the fact that its results constitute a central evidence base for public authorities, supporting the formulation of economic policies that are better aligned with the actual needs and financial situations of households in Spain.
Given its analytical relevance, and following a triennial frequency up to 2020, the EFF has been conducted on a biennial basis since 2022, allowing for more timely and up‑to‑date information on household finances.
The EFF 2024 is based on a particularly complex sample design, developed to ensure not only representativeness of the overall household population, but also of aggregate household wealth. Given the highly skewed distribution of wealth, and the fact that certain asset types are held by only a very small fraction of the population, the survey includes an oversampling of high‑wealth households, which is essential to accurately analyse the upper tail of the wealth distribution.
Another key feature of the EFF is its longitudinal component. In each wave, the survey interviews both newly selected households and households that participated in previous editions, following a system of linked sub‑panels. This design makes it possible to analyse developments in income, wealth and consumption over time, without compromising the cross‑sectional representativeness of the sample.
In order to combine these two features (high‑wealth oversampling and the panel component) with the required cross‑sectional representativeness of the population, each wave incorporates a refreshment sample, scientifically designed by the National Statistics Institute (INE).
The survey is also part of the Household Finance and Consumption Survey (HFCS) of the Eurosystem, which ensures methodological harmonisation and international comparability of the results.
The EFF questionnaire is organised into nine broad thematic sections, covering topics ranging from demographic characteristics to real and financial assets, debts, insurance and pensions, employment status, income, consumption and saving.
Data collection was carried out primarily through face‑to‑face household interviews, conducted by specially trained interviewers using CAPI (Computer‑Assisted Personal Interviewing), reflecting both the length and the sophistication of the questionnaire.
The complexity of the questionnaire represents one of the main challenges of the study. It includes a large number of economic and financial variables, many of which are sensitive and involve monetary amounts. This requires not only a high level of cooperation from households, but also advanced data‑collection tools and highly specialised interviewers. Interviews frequently last more than one hour and can extend significantly in households with more complex wealth structures.
Taken together, the highly demanding technical nature of the questionnaire, along with the sample design, the substantial response burden placed on households and the use of advanced statistical procedures, constitute one of the study’s key challenges and highlight the high level of technical and operational demands that characterise the EFF.
Since 2011, the Survey of Household Finances has been carried out through a collaboration between NORC at the University of Chicago and Verian, under the direction of the Banco de España.
NORC is responsible for the overall leadership of the project, drawing on its extensive international experience in household finance surveys, including the administration since 1992 of the equivalent survey in the United States, the Survey of Consumer Finances. Verian, in turn, is responsible for delivering the data collection in Spain, leading a particularly demanding fieldwork operation due both to the length and difficulty of the interviews (with an average duration of around 1.5 hours) and to the need to achieve high response rates in a wealth and income survey.
Achieving these response rates in a context of substantial respondent burden requires a very significant operational effort, together with the design and implementation of specific fieldwork protocols aimed at minimising non‑response and measurement error.
Within this framework, Verian has designed and implemented specific procedures for interviewer selection, training and supervision, together with proprietary tools for fieldwork management, questionnaire review and data quality control. These tools and procedures have been developed ad hoc to respond to the complexity of the study and to meet the Banco de España’s high quality standards.
Verian and NORC have jointly carried out the six most recent waves of the EFF (2011, 2014, 2017, 2020, 2022 and 2024), building a solid track record in the implementation of one of the most complex surveys within the Spanish statistical system.
Following the recent publication of the 2024 wave results, NORC and Verian are already putting in place the EFF 2026, once again under the direction of the Banco de España, continuing a long‑standing collaboration grounded in methodological rigour, fieldwork excellence and institutional trust.
The main results of the Survey of Household Finances 2024, recently released, are available on the Banco de España website:
https://www.bde.es/wbe/es/inicio/noticias/encuesta-financiera-de-las-familias-eff-2024.html