Foreigners to be counted, too! You must enumerate yourself in case you have a permanent or temporary residence in the Czech Republic for more than 90 days.
The 2021 Census begins at midnight on March 26–27, 2021. You can be counted online using the electronic form on the site or in the mobile app. The Online Census lets everyone to satisfy the legal obligation to be counted quickly and easily, without having to fill in paper census forms later.
All foreigners who have a permanent or temporary residence in the Czech Republic for over 90 days (regardless of whether they are currently in Czechia or not) are obliged to get counted. You must also fill in the form if you have been granted an asylum or you have stayed in our territory at midnight from 26th to 27th March 2021. The Census does not apply to diplomats and foreigners who are staying in the Czech Republic for less than 90 days (e.g. tourists).
Do not worry if you are not fluent in Czech? 7 language versions of the online form are available for your use (English, German, Polish, Russian, Ukrainian, Vietnamese and Romani). You can also use translations of the paper form in these languages.
You can find the answers to the most frequently asked questions about the Census here https://scitani.cz/csu/scitani2021/faq-en