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If your waiter or waitress is not the only person who’s served you in some way, it’s customary to tip the other servers, too.  For example, if you received the benefit of a wine steward, it’s customary to also tip 15 percent the cost of the bottle of wine. You can tip the coatroom attendant about $1 per coat or $2 for the parking valet or garage attendant, if you’ve left your car with them while dining. You can leave a smaller tip to your restaurant server if the food is served buffet style or the server brings you drinks only, but you should still tip between 10 and 15 percent. Some restaurants have washroom attendants; tip them 50 cents to $1. You might want to tip the headwaiter or captain separately also. When buying something over a counter, say morning coffee, you are generally not expected to tip. You can download apps to your smart phone that will calculate the tip for you if you plug in the amount of your bill.  Most smart phones also come with a calculator, which will allow you to calculate the tip yourself, depending on the amount you decide to leave. Various websites will calculate the tip for you. All you have to do is plug in the amount of your bill, and the percentage amount of the tip you want to leave.  In some states, the sales tax is about 5 percent. If that’s the case, you could multiply the sales tax listed on your bill by three in order to get 15 percent. If you used any coupons or discounts, calculate the tip based on how much you would've paid without it. Otherwise, you're punishing the waiter for the restaurant management's efforts to bring you in the door. Many servers absolutely rely on tips to survive. The fact they receive tips is calculated into a lower hourly wage in the first place.  It’s not uncommon for servers to make just over $2 an hour before they receive tips. They often make well under minimum wage. Although American states have different minimum wages, the federal minimum wage for tipped restaurant workers is just $2.13.  Some servers also are required to share or pool their tips at the end of the night or to contribute for tips to bartenders, lowering their overall haul. You are not legally required to leave a tip, however you’re being very unfair to your server if you do not do so. There’s no upside in being a jerk, but if you truly received awful service, you shouldn’t feel obligated to leave a full tip.  Try communicating with the server first, though, about what’s making you unhappy to give the server a chance to fix it. A tip to a server is meant to acknowledge good service. If your server ignored you, had a bad attitude, or served your food late, it’s OK to not leave a full tip. Assess how the food matched your order, whether the food was hot and fresh, how attentive the server was, how quickly your empty dishes were removed, and whether the server was courteous. You might want to explain the lack of a tip, in nice and constructive terms, on the bill when you pay the check, though. Some believe you should still give at least 10 percent even if you’ve received poor service.  Take care to determine whether the poor service was really the server’s fault. For example, perhaps the kitchen didn’t get the food to the server on time or management understaffed the restaurant. It can make a server’s day to be told you thought their service wasn’t just good but was impeccable. Why not let them know?  Write a little note on the bill when you pay your bill explaining what you thought the server did really well. Better yet, call over the manager and tell the manager about the good job the server did. Always treat your server to a smile and be kind and polite. Service jobs can be stressful enough without people taking out their bad days on the server!

Summary:
Tip other restaurant staff. Use a tip generating app. Realize why tipping matters. Leave a smaller tip for very poor service. Tell your server if the service was great.