Published Wednesday, 25 January 2012
The stores in Belfast, Bangor, Newry and Londonderry were shut down after last Sunday.
GameStop would not confirm how many staff have been affected.
A statement from the company said all customer credits will be honoured through their website or via stores in the Irish Republic, which have not been hit by the closures "at this time".
It continued: "The recent store closures in Northern Ireland are part of our plan, announced six months ago, to exit the UK market from a brick and mortar perspective and to focus on expanding our digital offerings in the UK.
"We started this process last year closing several stores in the UK, and these final closures completed the process.
"The stores in the Republic of Ireland are not affected at this time."
GameStop said it has experienced "tremendous sales growth" online and plans to extend its digital offerings going forward.