The study contains a comparison of monthly Harmonised Indices of Consumer Prices (HICP) in total and by individual divisions of the European Classification of Individual Consumption by Purpose (ECOIOP) for Poland, Czechia and the European Union (EU) in the years 2021-2022. The HICP is calculated according to the unified methodology applied in the UE and is used to measure inflation as well as to assess price stability in all EU member states.