The income which is taxable in the Czech Republic is always income paid out by Czech entities to their employees for work performed in the Czech territory; income from self-employment activities performed in the Czech territory or income from the rent of immovable property located in the Czech Republic. However, employment income paid out by a foreign entity, or dividends and interest from foreign sources might under certain conditions become subject to Czech taxation as well, even if they are received by an expatriate working in the Czech Republic or by a foreign individual performing here his self-employment activities. The magic number of “183 days stay” widely spread among expatriates as the only rule decisive for their taxation is, based on our experience, often interpreted incorrectly. Various types of income which should be taxed in the Czech Republic are sometimes not declared and taxed at all, what might lead to inconveniences for the particular expatriate in the future.