Remove “All Day” from Date field output in Drupal 7

We use the Date module for Drupal for a lot of the sites we develop, some require a date to be displayed, for example in a listing of events or “dates for your diary” but don’t want to list a time or have the date listed as an “All Day” event.

The answer is pretty simple, just add the below into your theme’s template.php file:

function [themename]_date_all_day_label() {
return "";