Who are the best tippers? According to a new survey by CreditCards.com, the most generous tippers are men, Republicans, Northeasterners and credit and debit card users. (Probably not among this group: Oklahoma City Thunder guard Andre Roberson, who last week left a $13.97 tip on a $487.13 bar tab and was promptly teased by teammates on Twitter.)

All these groups tip a median of 20% when dining at a restaurant, the CreditCards.com survey found. At the other end of the spectrum, women tip a median of 16% and Democrats, southerners and people who pay in cash tip a median of 15%.

So why do men and Republicans come out as the better tippers? Matt Schulz, CreditCards.com’s senior industry analyst, says it generally comes down to income.

(AP Photo/Elaine Thompson) More

“The more money you have, the more likely you are to leave a little more money on table at end of the night. Those groups – Republicans, men, Northeasterners – are higher income than their counterparts,” he said.

Men aren’t always so generous

About half of those who tip restaurant servers typically fall within a 16%-20% range for tips, and a tip amount of 11%-15% is a distant second. And we were a little shocked to learn that one out of five restaurant diners doesn’t leave gratuity at all, at least occasionally, according to the survey.

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