The European Central Bank has published a methodological report prepared by the Household Finance and Consumption Network for the 2023 wave of the Household Finance and Consumption Survey. The report explains how harmonised household-level data on assets, liabilities, income and consumption were collected and processed across the 20 euro area countries, as well as the Czech Republic and Hungary, using a sample of almost 90,000 households. While the most common reference period is 2023, the report notes that fieldwork and reference periods were not fully aligned across countries, with interviews conducted from 2022 to 2025 in some cases. The report sets out the main methodological architecture of the survey, including questionnaire design, fieldwork, sampling, weighting, editing, imputation, variance estimation and disclosure controls for microdata. It describes a decentralised model in which national central banks and statistical institutes collect the data while the ECB coordinates common definitions, quality checks and dissemination. All countries used probability sampling, most oversampled wealthier households to improve coverage of the upper tail of the wealth distribution, and 13 countries included a panel component. The report also highlights the use of administrative data in some countries, the role of weighting and calibration in addressing non-response, and the treatment of missing data through multiple stochastic imputation with five implicates for key wealth, income and consumption variables, while noting exceptions in some jurisdictions. It further explains that comparability across countries and waves can be affected by differences in survey modes, collection periods, administrative data use and coverage of affluent households. The report points to a companion publication for the substantive results of the 2023 wave. It also states that, from the sixth wave in 2026, the survey will be conducted under the ECB Guideline on statistical information to be reported on household wealth, income and consumption.