Junction One and The Outlet are for sale with a combined guide price of between £58m and £62m, according to property consultants CBRE.
The Outlet opened on the outskirts of Banbridge in County Down in 2007, but was effectively taken over by Ulster Bank in 2011.
Junction One opened near Antrim in 2004.
Ulster Bank also lent the money for that development.
The Outlet is currently held by an Ulster Bank company called West Register (Northern Ireland) Property.
It is a Northern Ireland branch of a group of companies set up by the bank's parent company RBS to hold "distressed properties".
Earlier this year another West Register firm sold the Richmond Centre in Londonderry.
The Outlet was opened in 2007 at a cost of £70m but struggled to fill all its units.
There are plans to switch part of its use from retail to leisure with a cinema and restaurants.
The last set of accounts for the company that holds Junction One valued the development at £7.85m, compared to a valuation of almost £80m in 2009.
Junction One Ltd had Ulster Bank borrowings of about £48m and its liabilities outweigh its assets by £53m.
Leona Barr, centre manager for Junction One, said: "We welcome that the Junction One complex is on the market as it brings great potential for future development and continued investment.
"We believe that the time is right for new owners to build on the success already achieved and to input additional investment to enable the complex to reach its full potential."
Two major out-of-town retail centres that struggled in the economic downturn have been placed on the market.