3 Number of the dwelling in the building:

The enumerator enters the answer for the dwellings in multi-dwelling buildings (block of flats, skyscraper, older multi-dwelling buildings).

The enumerator enters into appropriate fields the serial number of the dwelling, which is usually found above the entrance to the dwelling, or asks the people in the dwelling about it. The enumerator also enters other marks (e.g. letters, /, -, etc.), if the number has them.

All dwellings in multi-dwelling buildings must have the number of the dwelling. Dwellings that did not have the number got it before the 2002 Census. If the dwelling in a multi-dwelling building does not have a serial number (e.g. new entrance without a number, tenants do not want to attach it, etc.) but other dwellings in the building have it, persons in the dwelling or other tenants if the dwelling is empty tell the number to the enumerator. If no one can be asked about the dwelling's number, it is established on the basis of inferring from the numbers of neighbouring dwellings on the same floor or in the same building.

If no dwelling in a multi-dwelling building has a visible serial number of a dwelling, the enumerator must check with tenants if dwellings have serial numbers and enter it.

If no dwelling in a multi-dwelling building has a serial number and tenants do not have data on the serial number, the enumerator enters NN (no number).

In the so-called individual houses dwellings do not have separate numbers. This is also true in the case of several dwellings in the house.