Using WordPress ‘pre_user_last_name’ PHP filter

The ‘pre_user_last_name’ filter allows you to modify a user’s last name before the user is created or updated in WordPress.


$filtered_last_name = apply_filters( 'pre_user_last_name', $last_name );


  • $last_name (string) – The user’s last name.


Adding a Prefix to Last Name

function add_prefix_to_last_name( $last_name ) {
    return 'Dr. ' . $last_name;
add_filter( 'pre_user_last_name', 'add_prefix_to_last_name' );

This code adds the prefix “Dr. ” to the user’s last name before it is saved.

Capitalizing Last Name

function capitalize_last_name( $last_name ) {
    return strtoupper( $last_name );
add_filter( 'pre_user_last_name', 'capitalize_last_name' );

This code capitalizes the entire last name before it is saved.

Removing Whitespace

function remove_whitespace_from_last_name( $last_name ) {
    return preg_replace( '/\s+/\', '', $last_name );
add_filter( 'pre_user_last_name', 'remove_whitespace_from_last_name' );

This code removes all whitespace characters from the user’s last name before it is saved.

Replacing Hyphens with Spaces

function replace_hyphen_with_space( $last_name ) {
    return str_replace( '-', ' ', $last_name );
add_filter( 'pre_user_last_name', 'replace_hyphen_with_space' );

This code replaces any hyphens in the user’s last name with spaces before it is saved.

Abbreviating Last Name

function abbreviate_last_name( $last_name ) {
    return substr( $last_name, 0, 1 ) . '.';
add_filter( 'pre_user_last_name', 'abbreviate_last_name' );

This code abbreviates the user’s last name to the first letter followed by a period before it is saved.