The American Hotel & Lodging Association is the sole U.S. association representing all segments of the lodging industry has released a guide covering gratuity rates. Released just in time for the busy holiday travel season, the guide helps guests determine voluntary monetary ranges for services rendered by hotel staff throughout a guest’s stay.

Hotel Courtesy Shuttle Driver: Tip $1-2 per person of $4-5 per party.

Valet/Parking Attendant: Tip $1-5 when your car is delivered. Tipping when your car is parked is optional.

Bellstaff/Porters: Tip $1-5 per bag when you are escorted to your room (especially when your luggage is heavy or they prepare your room or show you around). Tip the same if you request bell staff service checking out.

Doorstaff: Tip $1-2 for getting a taxi. If they unload your luggage, tip in proportion to the amount and weight.

Concierge: Tip $1-5 per night. The tip should be left daily (preferable in an envelope or with a note so that it’s clear it’s for housekeeping).

Delivery of Special Items: For special requests (like an extra blanket), tip $2 for one item, $1 for one more. Tipping is not required for someone fixing something broken or brining something missing.

Room Service: A gratuity of 15-20% should be added if the hotel did not already include a room service charge on the bill.

Bartender: Tip 15-20% of the total beverage tab.

Waiter/Waitress: Tip 15% of the total bill, up to 20% for excellent service.