When it comes to tipping, most Americans believe they are better than average.
But some may be overestimating just how generous they are.
A new survey from TD Ameritrade finds that 81% of Americans rate themselves as great tippers.
Broken down by generation, baby boomers have the highest opinions of themselves, with 81% indicating they are great at tipping. That compares to 79% of Generation X and 79% of millennials who said the same.
But exactly when each generation tips varies with each situation.
One group of workers that almost everyone agrees should receive a tip: restaurant waiters and waitresses. Ninety-one percent of baby boomers said they typically leave a tip. Meanwhile, 81% of Gen Xers and 72% of millennials said the same.
Bartenders were next on the list, with 66% of boomers tipping. That compares to 62% of Gen X and 57% of millennials.
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Meanwhile, food delivery drivers were less likely to receive tips. In this case, however, millennials were the most likely to leave a gratuity. While 60% of that younger generation typically leave a tip, Gen Xers came in at 56% and boomers, 48%.
Boomers are also more likely to show their generosity to salon and spa workers, taxi drivers, parking attendants and hotel workers.
One type of worker who tends to get short shrift: fast food and coffee shop staff. Overall, just 26% of respondents said they typically leave extra money for those services. Gen X were the most likely to leave a gratuity, at 35%.
The survey also showed that many individuals don't agree on how a tip should be calculated. Most Gen Xers and millennials, at 55% and 58%, respectively, exclude tax when calculating gratuities. But just 47% of boomers do the same.
Etiquette expert Dianne Gottsman, author of "Modern Etiquette for a Better Life" and founder of The Protocol School of Texas in San Antonio, said she recommends making it easy by including the tax.
"It's not that much more, and it's simpler to figure out," Gottsman said.
The discrepancy is a testament to just how controversial tipping can be.
"There's no part of the dining experience that creates more debate than tipping," said Dara Luber, senior manager of retirement at TD Ameritrade. "There's so much debate on the tipping portion of the bill."
So how can you tell if you're erring on the side of being too stingy — or too generous?
"The best way to know what to tip is to do your homework," Gottsman said. "There is plenty information available and there is simply no excuse to not be informed."
Gottsman's general tipping recommendation for restaurants, bars and taxis is 15% to 20%. But rules for other situations, such as food delivery or hotel services, can vary. Plus, it always pays to check to see if gratuity is already included in a bill, she said.
It's also important to note that different cultures have their own tipping rules, Gottsman pointed out. In Canada, expectations are similar to the U.S. and generally call for tips of 15% to 20% of the bill. Meanwhile, in Asia, tipping can be perceived as rude, depending on the situation. But workers in the travel industry might be more receptive to gratuities.
TD Ameritrade's online survey was conducted between October and November 2019. It included 1,011 adults ages 23 and up who have at least $10,000 in investable assets.