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Restaurants
Tipping is customary in restaurants having traditional table service. While the amount of a tip is at the discretion of the person receiving the service, the customary tip until the 1980's was from 10 to 15 percent of the total bill before tax, for good to excellent service, and since then has risen to 15 to 20%. The higher percentages are often expected at more expensive establishments.
For large groups, such as six or more, many restaurants add a standard predetermined service charge (~18%) in lieu of the gratuity. If service to a large party is poor, a customer may try to negotiate an alternate service charge with management.
Standard gratuities are not given at buffet-style restaurants. However, if patrons order beverages from the server, then a nominal tip such as $1 each may be considered. Some restaurants add a standard service charge even for buffet service for large parties, though many consider this inappropriate when there is no table service.
Tipping at fast food restaurants and coffeehouses such as Starbucks (where there is no table service), is not necessary, despite the common appearance of tip jars (a.k.a. "guilt cans"[citation needed]).
Bars
When purchasing alcoholic beverages at a bar it is customary to tip. One dollar per drink is customary. If a bartender is taking special care to take and fill your drink orders quickly at a busy bar where others may be waiting for service, a tip in the higher range is appropriate. In some cases drink orders felt to be more complex than a draught beer or simple mixed cocktail (such as a mojito -- which takes more time and attention to prepare) also warrant a tip greater than a dollar per drink.
Hotels
Bellmen are customarily tipped on a basis of a fixed amount (usually a few dollars) per bag carried, and are often tipped for deliveries (food, boxes, faxes) as well. Room-service personnel at most American hotels expect tips, anywhere between 10% to 15% of the price (before tax) of what was ordered. It should be noted that many hotels automatically add a service fee to room service meals. The customer should verify this in order to avoid double tipping. A small tip for the housekeeping staff is discretionary. Tipping the front desk staff is almost never done unless the service is exceptional
Taxicabs
Most U.S. guides recommend 15% of the fare, more for extra services or heavy luggage
Delivered Meals
The driver is often tipped 10 to 20%. A greater tip can be given if the driver has to drive in inclement weather (e.g. snow), carry heavy loads, and/or climb flights of stairs. This issue is complicated by establishments sometimes charging a delivery fee (usually $1-2 per order), which is similar to a service charge, although in many cases (e.g. pizza delivery establishments such as Dominos) the driver gets no part of the delivery fee, and may be under-tipped as a result
Car Washes
If a person hand dries the car, he/she is sometimes tipped.
Hairdressing
For a haircut or salon service, it is customary to tip the barber or stylist 10% to 20%
Valets
At restaurants or hotels where the customer valets their car, it is customary to tip the valet $2-5 or occasionally more at high-class establishments.