Gratuities are an expected part of the cost for many services; be sure to budget accordingly. Thinkstock By Stacy Rapacon, Online Editor Updated January 2015 Tipping can be stressful. Not only does it involve math, but it also requires you to know all the tiny details of the unspoken agreement between you and your service provider in any given situation. And if you get it wrong, you risk insulting someone, looking like a cheapskate or wasting money. "When we feel uncomfortable and uncertain, we sometimes overtip because we don't want to come across as looking cheap," says Diane Gottsman, owner of The Protocol School of Texas. "It's so important to know how to show gratitude" and to budget accordingly.See Also: How Much Should You Tip? Keep in mind that many workers rely on gratuities to make a decent living. For example, according to compensation research firm Payscale, waiters and waitresses rely on tips for 58% of their income. Skipping the tip at a restaurant would severely slash your server's daily pay. Know Whom to Tip and How Much They Deserve Typically, you're expected to leave 15% to 20% of the pretax bill for your waiter at a sit-down restaurant in the U.S. According to Zagat, the average tip bumps up against the top of that range at 19.7%. At a buffet-style restaurant, you can dial back the tip and leave just 10% of the cost, according to the etiquette gurus of the Emily Post Institute. If you opt to order in, you should tip the delivery person 10% to 15% of the tab — reaching for that higher limit if you have a large or complicated order or if you receive particularly quick service — with a minimum of $3. People working the counter for take-out do not expect a tip. But, of course, a contribution to the tip jar would be welcome — especially because these workers are often servers missing out on tips from table service, says Gottsman. She recommends giving 10%. Bartenders should get $1 or $2 per drink — even if you're just drinking water (because you're still taking up prime real estate at the bar, says Gottsman) — or 15% to 20% of the tab. Advertisement Outside of the food industry, you should also tip barbers, stylists, nail technicians, massage therapists and other salon and spa professionals about 15% to 20% each. You might also consider giving something extra to movers and furniture-delivery people, a casino's blackjack dealer, taxi drivers, your wedding DJ — basically, any service provider who is not a salaried professional. "If you aren't sure if the service worker accepts tips, you can always offer a gratuity if they have done something noteworthy," says Gottsman. Consider whether they've been courteous, attentive and efficient; how you feel about their work should help you decide whether to offer a tip. (For more on whom to tip, take our quiz, How Much Should You Tip?) And don't forget all the people you need to tip while you travel and during the holiday season. But save your cash and skip the tip when it comes to salaried professionals, such as doctors, lawyers, accountants, teachers and plumbers. They don't expect anything extra and don't rely on gratuities to make a livable wage. If you feel compelled to show them your gratitude, a gift or note would be more appropriate. Handle Tipping for Bad Service Appropriately Your most gracious tips should be reserved for exemplary service, and gratuities should slide with the service quality. Still, though the topic is widely debated among consumers, our etiquette experts agree you should always leave something. After a bad dining experience, Gottsman says 10% is the bare minimum you should leave, while Lizzie Post of the Emily Post Institute recommends you stick with the 15% lower limit of the standard tip. (See Why You Shouldn't Overtip for another opinion.) Why tip at all for bad service? Think of it this way: Even a cubicle dweller is prone to bad days on which he doesn't smile as much as his boss would like or he seems a little distracted, but he still gets his job done. That office employee's pay would not be docked at all for his lackluster performance — let alone by 58%. Plus, says Post, "some of the things that upset you about the meal might not be the server's fault." Advertisement On top of minimizing your tip, you should take the time to speak with the manager — "away from the table," notes Gottsman — to explain your meager tip and complain about the subpar treatment you received. Voicing your criticism gives the manager a heads-up on a possibly big problem for the restaurant and allows the server to try to do better the next time. "All of us get performance reviews at work," says Post, and this is how waiters get theirs. Understand Different Tipping Policies The rules are different overseas. In Japanese culture, for example, tipping is not the norm and would just "be a source of confusion," says Gottsman. And across the pond in Europe, the change from your bill or up to 5% is an acceptable tip for sit-down dining. Some U.S. restaurants have adopted these customs. For example, Sushi Yasuda in New York City keeps its policies in line with typical Japanese customs and nixes tips. High-end establishments Per Se, also in New York, and the French Laundry, in Napa Valley (both owned by chef Thomas Keller), opt to automatically include a service charge on every bill. And many places automatically tack on a tip for large parties. Be sure to check your restaurant's practices before you accidentally overtip.