He will join Luton Town for a fee thought to be £375,000 but Swindon won't any get money from the sell on clause as it wasn't sold on for a big enough profit.
Parkin spent three years at the County Ground between 2002 and 2005 and scored 67 goals in the 120 games he played for Swindon in that time making him Swindon highest goal scorer of recent times.