See NCTE's Name Changes for Kids in Florida site for information about legal name changes for minors under the age of 18. The minimum age varies by type of change requested: To create a new last name, you must be at least 17 years old. However, if you can provide proof of having another first name used exclusively after your birth (for example, a middle name), you may be able to request this change before your 18th birthday. To replace your current name with an equivalent name that differs only in gender, you must be at least 16 years old. This rule applies even if you were born with a male name or a female name. For example, if you were named Michael but want to become Sarah, you must show proof of having another first name used exclusively after your birth (for example, a middle name) to be granted this change. To remove your parent(s)'s names from your own, you must be at least 13 years old. You cannot do this on your own; instead, you must appear in court with a parent or guardian who will answer questions about your identity and intentions. Name changes are usually done through a notary public or clerk of court.