Shoppers heading to the stores after Christmas should be on the lookout for deals.

'Tis the morning after Christmas, which means there can only be one thing left to do: take back that sweater from Grandma that's two sizes too big, and see if you can score any deals on the items left on your list.

So how tough will it be to make your exchanges or get a refund this year? Personal finance site GOBankingRates.com ranked the return policies of leading U.S. retailers.

Costco, Nordstrom and Walmart ranked high on the list of the most lenient retailers when it comes to accepting returns.

Christmas Gift Tips: How to Protect Your Tech Gadgets (And Get Them to Work!)

The most restrictive stores? Sears and Best Buy, where shoppers have only until January 15 to make returns, both made that list.

Best Buy stores across the country are opening their doors at 7 a.m. today and not closing them until 11 p.m. to accommodate the rush.

Online Retailers Tackle High Rate of Customer Returns

Lucky for post-Christmas shoppers, there are deals to be had as retailers try to increase their bottom line.

Initial indications point to this as the worst Christmas shopping season since 2009, with in-store retail sales down 3 percent last week and foot traffic down 21 percent over last year, ShopperTrak reported.

UPS Overload Leaves Miffed Customers Short of Presents, Meals

After Christmas, retailers are willing to give shoppers a bargain to clear out their merchandise to make way for the new.

"You know you're getting a very good deal because that week after Christmas, retailers look to go through merchandise in order to transition to the next season's goods," said retail analyst Dana Tesley.

Macy's has been advertising door-buster sales for its one-day-only sale today, while Amazon.com has already started offering its so-called "Year End Deals" of up to 70 percent off.

Clothing retailer Old Navy is launching its after-holiday sale with markdowns of up to 75 percent in-store and 60 percent online.