Some large companies give away piles of cash, but boast budgets so big they can easily afford it. Smaller companies may give lesser amounts, but they sacrifice more to do so. It's the difference between a millionaire giving away $10,000 and a teacher giving away $10,000.

To determine America's Most Generous Corporations, we compiled two different lists. First, we looked at overall cash donations--who wrote the largest checks. Second, since most companies budget their donations on the previous year's income, we looked at 2007 cash giving as a percentage of 2006 operating income--who gave the biggest piece of their pie.

Financial information was provided by The Chronicle of Philanthropy, a bi-weekly publication for the nonprofit community, which performs an annual survey of companies asking the nation's largest companies about their giving habits. The 78 corporations tracked in the survey gave away a combined $3.8 billion in 2007, up from $3.6 billion in 2006.

The No. 1 most generous company overall, Wal-Mart Stores, gave away $301 million in 2007, including total cash donations from the company foundation, and excluding free product and service offerings, otherwise called "in-kind" donations. That amounts to 1.3% of the company's 2006 operating income.

Beneficiaries of Wal-Mart's goodwill include the Children's Miracle Network, America's Second Harvest, the Salvation Army, the American Red Cross, the United Way of America and the National Fish and Wildlife Foundation.

Bank of America was the second biggest overall cash contributor, giving $211 million in donations last year, to causes including Habitat for Humanity International. Exxon Mobil came in third, donating $173 million in cash to programs including the Texas-based Community Summer Jobs Program.

The list of companies that gave the largest portion of their income looks a little different. Supermarket owner and operator Kroger is ranked No. 1 in cash donations as a percentage of operating income.

The company donated 1.7% of its $3.3 billion operating income, or $57 million in cash, to causes including the Boy Scouts and Girl Scouts of America, Feeding America, Second Helpings and the Salvation Army.

The second most proportionally generous company, Tyson Foods, gave 1.6% of its operating income, or $8 million, to charities including Meals on Wheels and the Ronald McDonald House. Pharmaceutical giant Bristol-Myers Squibb came in third place, giving 1.4% of its income, or $59 million, to beneficiaries like the Baylor College of Medicine Pediatric AIDS Corps.

Traditionally, pharmaceutical companies give away the most in-kind donations, or free products and services. For instance, while Bristol-Myers was one of the most generous companies in 2007 in terms of cash, it also gave $281 million in products.

Pfizer [Get Quote] gave the most in products at $1.7 billion, ahead of Merck ($766 million) and Abbott Laboratories ($345 million).

Tech companies get in on the in-kind action as well; Microsoft donated $322 million worth of software and services in 2007. That's in addition to $110 million in cash donations, representing 0.5% of operating income--enough to put the company at ninth place in overall cash handouts.

Despite global economic slowdowns, Microsoft says it isn't planning to cut back on charity, according to Akhtar Badshah, senior director of global community affairs. "We don't see that as a company, we will reduce our investments in the community," he says. "Our challenge is how do we increase investment in community, given needs are going to be even greater right now."

The story's the same at Johnson & Johnson, where spokesman Shaun Mickus says the company expects its level of giving to remain "fairly consistent."

J&J came in fifth on the overall cash contributions list, giving away $127 million, or 0.7% of operating income. The company's cash donations were up 10% from $115 million in 2006.

"It's always hard to forecast this kind of stuff year over year," says Mickus. But Johnson & Johnson has withstood rough economic times before and remained a consistent giver. "This is just part of what we do. We're not about to stop." 

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