DENVER - Problems with gift returns are common during this time of year, and while some stores loosen their return policies during the holiday season, the Better Business Bureau warns that some stores could be tightening policies because of an increase in return fraud.

In a survey conducted by the National Retail Federation, retailers estimate that 4.6 percent of holiday returns are fraudulent, costing the retail industry an estimated $2.9 billion.

Return fraud comes in many forms, but the main methods involve purchasing merchandise for short-term use and then returning the item, returning stolen merchandise, or using reused, stolen or falsified receipts to return merchandise for a profit.

To put yourself and your gift recipients in the best position for a happy return or exchange, the Better Business Bureau offers this advice:

Do not assume that regular return policies apply to sale or clearance items. Some merchants consider the sale of such items to be final. If you are the gift recipient, do not assume you have the right to return or exchange an unwanted present. Like the shopper, you are bound by the merchant's return policy. Health regulations, which can prohibit the return of hats and intimate apparel, also may apply.

Ask about restocking fees. Some merchants charge a restocking or "open box" fee for returns of electronic products or large-ticket items. A restocking fee can be as high as 25 percent of the purchase.

Look for a posted return policy when shopping online. If returns are permitted, ask what procedures and time frames need to be followed. Find out whether shipping fees are charged for returning items and whether shipping costs or restocking fees are deducted from the price of returned items.

Save your receipt. Save all receipts until at least a month after the holidays. Keep items in their original packaging and leave tags on clothing until you are certain the items are keepers.

Time your returns to avoid hassles. Return lines can be lengthy immediately after the holidays, but don't wait too long to return items. Pick a time when the store is unlikely to be crowded, and be polite when talking to customer service clerks. If you are a regular customer or have a store credit account, mention that as you discuss return options. Merchants are usually willing to accommodate loyal customers.