Spanish surname

Spanish naming customs are historical traditions for naming children practised in Spain. According to these customs, a person's name consists of a given name (simple or composite) followed by two family names (surnames). The first surname is usually the father's first surname, and the second the mother's first surname. In recent years, the order of the surnames can be reversed at birth if it is so decided by the parents. Often, the practice is to use one given name and the first surname only (e.g. Miguel de Unamuno), with the full name being used in legal, formal, and documentary matters, or for disambiguation when the first surname is very common (e.g. Federico García Lorca, Gabriel García Márquez).

Currently in Spain, people bear a single or composite given name (nombre) and two surnames (apellidos).

A composite given name comprises two (or more) single names; for example Juan Pablo is considered not to be a first and a second forename, but a single composite forename.

The two surnames refer to each of the parental families. Traditionally, a person's first surname is the father's first surname (apellido paterno), and the second one is the mother's first surname (apellido materno). For example, if a man named Eduardo Fernández Garrido marries a woman named María Dolores Martínez Ruiz and they have a child named José, there are several legal options, but their child would most usually be known as José Fernández Martínez.

However, gender equality law has allowed surname transposition since 1999, subject to the condition that every sibling must bear the same surname order recorded in the Registro Civil (civil registry), but there have been legal exceptions. From 2013, if the parents of a child were unable to agree on order of surnames, an official would decide which is to come first, with the default being the paternal name. Since June 2017, the paternal name in first order stopped being the default, and parents are required to sign an agreement where the name order is expressed explicitly. The law also grants a person the option, upon reaching adulthood, of reversing the order of their surnames. The law applies only to Spanish citizens; people of other nationalities get the surname indicated by the law in their original country.

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