If you no­tify the mu­nic­i­pal­ity that you are a mem­ber of one of the two na­tional churches (Roman Catholic or Protes­tant (Re­formed)) you will have to pay church tax (Kirchen­s­teuer).

This tax is an ad­di­tional 15% of the basic can­tonal tax for Roman Catholics and 10% for mem­bers of Protes­tant (Re­formed) churches. Church tax is levied to­gether with in­come and wealth tax on the same tax cal­cu­la­tion.