As shoppers gear up for the holidays, they may find that getting a deal increasingly involves giving to charity, too.

Experts say retailers, daily deal sites and other businesses are running more promotions this year that entail an up-front donation, or send part of the purchase to a nonprofit. Plus, the number of deal sites that give a portion of every sale to charity has more than quadrupled over the past year, says Jack Vonder Heide, president of market research firm Technology Briefing Centers. That's just 30 or so sites in a burgeoning market of 600, but still represents substantial growth year-over-year for such a niche idea. "We're seeing a big spike in charitable-related sites as the holidays approach," he says.

 

Experts Explain: How to Choose a Charity

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Before you give this holiday season, make sure you know exactly where your money is going.

This surge in generosity is not entirely altruistic. Repeated studies have shown that consumers gravitate toward purchases that include some kind of charitable contribution, says Ken Berger, chief executive of Charity Navigator, a site that evaluates nonprofits' finances. That's key this year, considering National Retail Federation projections for a 10% cut in the average shopper's holiday spending. "It drives volume, which is important," says Vonder Heide. "The charity angle is a good way to do it because individuals want to give, but economic times of late have precluded them from giving as much as they'd like. This lets them both get the deal and give back."

On the daily deal front, shoppers can expect to see more offers from sites like LivingSocial.com, which plans to donate to charity some of its proceeds from sales Dec. 5-16. Other sites may let partner businesses do the donating. For example, through Nov. 30, Daily Candy Deals is charging $25 for a $50 voucher to Blanket America, a linen company that donates a blanket to charities supporting the homeless for each item that it sells. So if someone uses that voucher to buy two $30 throws, their purchase generates a donation of two blankets. PopSugar Shop http://shop.popsugar.com offers deals at OneHope Wine, which donates half of profits to partner charities benefiting a variety of causes. Through Nov. 24, shoppers can buy a $40 voucher for $19 or a $75 voucher for $35.

Consumers may also see deals at their local businesses and national retailers. Home goods store CB2 offers a 15% discount on one in-store purchase for bringing seven nonperishable food items into the store by Nov. 28. Online shoppers can grab the deal the opting to make a $10 donation to Share Our Strength at checkout. Deals aren't limited to shopping, either. In a recent promotion, Mets fans that made a donation of 10 or more nonperishable food items got a voucher for two free 2012 games, and Chase is reprising a bonus offer for 5% cash back on up to $1,500 in charitable contributions through Dec. 31.

But consumers should be careful not to get too wrapped up in the charitable aspect of such offers. Berger recommends reading the details of the program or deal to determine how much of a purchase the charity might actually be getting. That can often be tough to calculate, so think of the charitable contribution as just an added bonus that isn't part of your overall giving plan. Or the sole reason for buying. "Make your selections based on the best product for the best price," he says. It's often tough to calculate just how much is going to the charity, so And in most cases, it's the business or retailer that can claim the charitable deduction come tax time -- not the person purchasing the voucher.

It's possible, however, to boost the charitable impact of a purchase. Look for sites or deals that offer matching donations from partner retailers, says Vonder Heide. Macy's "Thanks for Sharing Program," which offers store cardholders a 10% credit on purchases through Dec. 31 in exchange for a $25 donation, pledges to donate another $10 -- up to $15 million total for every sign-up. Deal site SharingSpree.com gives 10% of every offer to a rotating selection of nonprofit, but chief executive Ron Sapp says users who add a favorite to their profile can designate an extra 5% donation to them with every purchase.