The parents must determine the given name of a child through a declaration of consent within one month of birth. If the father is not known, or if the child is born to an unmarried woman and if paternity is not determined by the end of the period, the mother’s declaration is sufficient to determine the name. If this period expires and the parent (or parents) does not give the child a name, the competent registry of births, deaths and marriages will notify the court, which will decide on the name.
A child who is a citizen of the Czech Republic and whose parents have Czech citizenship may have a maximum of two given names. In such a case, both must be used in official communication. These two names must not be the same.
A statement may be made before the competent registry of births, deaths and marriages that a citizen who has previously had one name will use two names. In the case of a minor under the age of fifteen, this declaration will be made by their legal representatives. If the child is over the age of fifteen, their consent is required for a second name.
Only given names that exist and that have a correct spelling can be entered as given names. The law prohibits the registration of names that are distorted, diminutive, or domestic. In the same way, a female name cannot be registered for a male person and vice versa.
Adoptive parents may, within six months from the legal force of the adoption decision, but no later than when the adopted person reaches the age of majority, choose for the child a different name or names than the one entered in the registry through a mutual declaration before the registry of births, deaths and marriages. If only one name is registered, they can choose another. If the adopted child is older than 15, they must attach their consent to the declaration.