Released at no charge, on the day (5)
I believe the answer is:
freed
'released' is the definition.
('free' can be a synonym of 'release')
'no charge on the day' is the wordplay.
'no charge' becomes 'free' (synonyms).
'on' is a charade indicator (letters next to each other) (in a down clue, letters appear on others).
'the day' becomes 'd' (abbreviation for day).
'free'+'d'='FREED'
'at' is the link.
(Other definitions for freed that I've seen before include "Released" , "Defer being liberated" , "Untied" , "Emancipated, let loose" .)