Not tipping at a restaurant, or even just tipping badly, can be a sure-fire way to go viral on social media. That's because many servers in the U.S. depend on tips for more than half of their earnings. And it's because, as "Shark Tank" investor Kevin O'Leary says, "tipping is an investment."
"You want to establish a relationship with the waitstaff to take care of you," he says.
That same principle applies to tipping around the holidays: You tip to say thanks and to maintain good relationships. And because a lot of the service workers who traditionally get tips over the holidays rely on, or could really use, that extra cash.
Of all the folks you interact with on a regular basis, though, who expects and/or needs a tip this holiday season, and how much are you supposed to give them? Etiquette experts are here to help.
This is a general guide to whom and how much you should tip, sourced from Elaine Swann, founder of The Swann School of Protocol, as well as the N.Y. School of Etiquette and The Emily Post Institute. In most cases, cash or gifts are both acceptable.
"You should most certainly tip individuals who have helped you or assisted you in some way or fashion throughout the year," Swann tells CNBC Make It. "Most of these individuals tend to be in the service-based industry."
After all, she says, "those individuals, more often than not, go above and beyond the dollar amount that they're providing." Maybe your barber throws in an extra trim every now and then pro bono, or your doorman keeps a package safe for you while you're away.
Swann's rule is, when it comes to people who charge you a consistent fee, give them the cost of one service. If you pay your personal trainer $100 per session, for instance, that's how much you should tip.
As for people who you don't usually pay yourself, there are broad ranges of how much you should give. Where the appropriate tip amount falls within a given range may vary "based on the type of establishment, regional customs, and your own budget," according to The Emily Post Institute's holiday tipping guidelines.
Tips in big cities tend to be larger because the cost of living is higher. Similarly, if you live in a luxury apartment, doormen might expect something on the higher end of the $15 to $150 range.
Note that federal employees are generally not allowed to accept cash, she says. If you know and what to thank your letter-carrier, or if you want to tip your child's public school teacher, you can get them a small gift.
And if spending any money for a tip is a beyond your means, it's also acceptable to give a homemade gift, etiquette experts agree. That kind of effort can end up feeling more meaningful, too.
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