Our paper focuses on the tax progressivity and nonreligion in central and eastern Europe using an example of the Czech Republic, one of the most atheistic countries in the world. Religion might imply formal affiliation with a certain confession or active church attendance, but it might also become a determinant of taxation preferences. We employ ordinal regression analyses to study direct and mediation effects of both church affiliation and church attendance on a representative sample from the Czech Republic (n = 1924, 54.8% female, aged 18–95, M ± SD: 52.0 ± 16.9; 19.4% with higher education) controlling for employment status, social class and socio-demographics. The results suggest that neither church affiliation nor church attendance were related to desired income tax progressivity; social class plaid the most important role. The frequency of church attendance was significantly related to the perceived adequacy of taxation of higher incomes, where the more respondents attended the religious services, the more they believed that the taxes on the rich are too high. However, the churches’ ideas to help the needy were manifested in the preferences for international tax progressivity, where the frequent churchgoers were more inclined to the idea that the rich countries should pay additional taxes to help the poor countries. These controversial results may indicate the rivalrous position of the church and the state in the Czech Republic in terms of taxation of the wealthy. We suggest that under the condition of no church tax, the state taxation of the rich may be viewed as diverting funds, which could otherwise be directed to the church. These results might be of some interest to the state, the church and to the academic researchers alike and significantly contribute to the discussion on specific features of nonreligiosity in central and eastern Europe.