How Much Should I Tip While Traveling?

To and From the Airport

Taxi or Limo Drivers	15% - 20% of the bill.
Hotel Courtesy Shuttle Drivers	$1-$2 per person, extra if he handles luggage.
Porter	$1 per bag, $2 for very heavy bags.
Sky Cap	$1 per bag, $2 for very heavy bags. Additional $1-$2 optional for curbside check in.

At the Hotel

Bell Man or Bell Captain	$1 per bag, $2 for very heavy bags.
Maids	$1-$3 per day depending on the amount of mess and the grade of the hotel, more ($5-$10 a day) for high-end hotels. Leave the tip someplace where it's clear that it's a tip -- on the pillow or on the desk with a note.
Room Service	15%-20%, depending on service. Service is often already added.
Parking Attendant	$1-$2, usually when they bring you your car.
Doorman	Tip $1 if the doorman hails you a cab. If he also carries your bags, tip $1-$2 per bag.
Concierge	If he gives you advice, tipping is not necessary. If he does something out of the way, like getting difficult restaurant reservations or tickets, $5-$20 (or more) is the norm, depending on the difficulty. You can tip at the time of service or at the end of your stay.
Other Courtesy Items	If you request something delivered to your room, like a hair dryer or an iron, tip $1 per item received.

Touring

Tour Guides

If you are pleased with the tour, you can tip $2-$5 to the tour guide for a full day tour, $1-$2 to the driver. Tip a private guide more.

Cruises

Tour Guides

Some cruises have an automatic tipping program totalling $10-$13 a day. Read our guidelines for tipping a cruise staff.

Articles:

Tipping Guidelines for Cruises