Saving the children, the trees, and the piping plover are all good causes, but how can you tell which of the estimated 1.8 million U.S. charities vying for your dollars are most worthy? Check their ratings on three nonprofit sites: www.charitynavigator.org, www.give.org, and www.guidestar.org. If the one you’re looking for isn’t listed, it may be bogus, or it may simply be new. The American Institute of Philanthropy says your money will be used most effectively by an established charity, but if you’re still interested in an unlisted one, ask to see copies of its most recent tax return (IRS Form 990), which it is required by law to provide to anyone who asks. Then divide line 13 by line 17 to find out what percentage of the money it spends goes toward funding research or providing programs and services, rather than covering administrative and fund-raising costs.

“People should focus on charities that spend at least 75 percent of their budgets on programs and services,” advises Charity Navigator spokesperson Sandra Miniutti. “The most effective ones are even more efficient.” You work hard for your money; don’t let the wrong charity throw any of it out the window.