When you’re saving up for a trip, you probably factor in the cost of airfare, hotel accommodations, food and entertainment into your vacation budget.

But do you set aside money for the service workers who go out of the way to make your trip better?

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Tipping while traveling: Who you need to tip!

There’s a lot of confusion about the people you should tip (and the amount), so many of us end up either tipping too much or not enough.

Also for many people, tipping is a subjective concept — based on the quality of the service provided.

But in general, experts say there are some service providers you should always consider tipping because that “extra” money is a large portion of what those workers depend on.

“Tipping etiquette offers a guideline and a good opportunity to show respect, consideration and gratitude for services rendered,” said etiquette expert Diane Gottsman, founder of The Protocol School of Texas. “It’s never appropriate to overlook gratuity when service providers are dependent on it as part of their livelihood.”

So which service workers do you tip and how much? Gottsman, author of the new book “Modern Etiquette for a Better Life,” provided Clark.com with these easy-to-follow guidelines!

Don’t forget to tip these 10 service providers

1. Airport shuttle driver: Even if you don’t have luggage, tip $1 to $2 for the ride to the hotel. Provide an extra gratuity if the driver assists you with bags.

2. Cab driver: 15% to 20%.

3. Valet: Tip $2 to $3 when you pick up your car, not when you drop it off.

4. Doorman: No tip necessary just for saying hello, but give $2 or $3 if the doorman provides special assistance.

5. Hotel concierge: Tip $5 to $10 for general theater tickets or dinner reservations, and more for special services. No tip is required for simple directions.

6. Bellman: $1 per bag if the bellman takes luggage to your room.

7. Room service: 15% to 20% of the meal, but check the bill to see if the gratuity is already included. No extra tip is required in that case.

8. Restaurant server: 15% to 18% is standard, but leave 20% or higher for exceptional service.

9. Spa/massage worker: 15% to 20% of the service price.

10. Housekeeper: Leave $2 to $3 or $1 per guest after five people. Tip daily because housekeeping staff can change from day-to-day.

To be clear, these are just guidelines. There are no hard and fast rules.

For example, one time I left my bag with a bellman for storage and figured that I only needed to tip him when I returned to pick up my luggage.

But he was clearly expecting a tip, and he even told me his shift was about to end.

When I got back to the hotel after a day of sightseeing in New York City, I retrieved my bag and tipped a different bellman a few bucks.

The only problem? The handle on my bag was intentionally broken. I learned my lesson!

Bottom line: Before your next vacation, make sure that you have plenty of $1 and $5 bills on hand to show service workers that you appreciate their hard work.

Read more of Gottsman’s etiquette advice on her blog.

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