But "must" is not the same as "should": You will most certainly be in the minority if you don't offer the service people in your life a tip.
Moving house, for example? If you get help, you'll probably want to tip each crew member between $20 and $40 — and the lead mover between $50 and $100. Or you might want to peg your tip to 5% of the bill.
As for Uber drivers, you are not obligated to hand over cash. But if skipping the tip feels wrong, consider tipping according to the same rules of thumb for other taxicab drivers: 10%, 15% or 20% (or even more) is customary, depending on how expensive a city you are in and whether the driver helps you with bags.
Bartenders should get anywhere from $1 for a cheap beer at a casual joint to 20% at a higher-end place where you've racked up a big bill.
Now, your money might be tight. But remember that most of your service workers make less than the median annual wage of $36,200. That means that regular tips are an important income supplement — and a holiday bonus equivalent to one session of service (or a week's pay, whatever is easiest) could go a long way.
Here's a guide to tipping the many service people in your life.
How much do you tip a doorman?
Building staff — including doormen, porters, supers, maintenance personnel and garage attendants — especially in New York and other major cities, are the primary recipients of tips.
According to a survey of doormen by Brick Underground, they get between $3,000 to $13,000 in annual tips.
A survey of residents, also by Brick Underground, in 2015 showed that the gratuities dolled out by owners in doorman buildings ranged between $0 and more than $2,500. But the biggest group, 20%, tipped between $250 to $500.
Owners in non-doorman buildings (meaning the tips went to supers and maintenance people) ranged from $0 to $2,000, with the most, 63%, giving less than $250.
Renters tend to give less than owners because often they've lived there less time and they may have less income. According to the survey, the largest groups of renters in doorman and non-doorman buildings gave less than $250.
Most doormen said that the average tip is $25 to $75 per apartment. Although they made a point of saying that it all depends on how much attention you need from the building staff. Say, you work at home and get a lot of deliveries, you are in and out with your dog, you have kids and rely on the staff to help with strollers? You should tip accordingly.
According to the doormen themselves it doesn't have to be cash. They say they enjoy food. "Lots of people will also give food," a doorman said at a Prospect Heights rental building. "In January, I'm still eating what they gave me. Others will give bottles of wine and cheese baskets."
Or a thoughtful gift: "Sometimes little gifts are better than money," another doorman said in a large Union Square rental building. "During the winter, I sometimes get hats, scarves, gloves. One nice tenant got me a great tie. It's the little things, too."
But most doormen in the survey agreed that tipping pools are too impersonal.
"I like getting a special gift with a card from someone, a nice note," said a doorman in a luxury condo building in Hunter's Point, Queens.
The staff likes to be shown that they are appreciated.
"Tips depend on the person, and you might get a couple hundred, but the most rewarding thing is when people say thank you for your job," a doorman said at a Prospect Heights co-op. "The money, it helps, but that's not the most important."
Placing your cash in a holiday card is not only more personal and proper etiquette, it also ensures that your gift does not get lost in the holiday shuffle.
For more detailed discussion of tipping building staff — including "my 'doormen' are really security guards, do I need to tip them?" (go light), "can I tip my favorite doorman more than the rest?" (sure) and "can I deduct my tip as a business expense if I work from home?" (some of it) — go to Brick Underground's guide to building tips.
How much do you tip a maid or house cleaner?
A regular cleaning service that comes to your place, whether it is an independent individual or several people working for a larger company, would appreciate a double payment at the end of the year.
If the crew comes every two weeks and you pay them $100, give them $200 for a holiday tip. Some people give two visits-worth as a tip.
Maids and housekeepers make a median annual salary of $20,740.
Another way to think about it is if you gave a 10% to 15% tip per visit throughout the year, as some people do.
To make an equivalent year-end gift on the example above you'd gift $260 at the end of the year.
Some people also like to give a personal gift like a bag or a hat and gloves set or a gift of basket of food or treats.
How much do you tip a nanny?
A standard year-end expression of appreciation for a full-time nanny or caregiver for your children is one-weeks pay. Or two-weeks if you can swing it. Or even better: one-week's pay and one week's vacation with pay.
Nannies' pay varies by location and by type of employment, but on the low end they make an average of $18,835 a year.
The amount you give as a year end tip will depend on your particular child-care situation — is it a nanny-share that you're going in on with another family? is this a live-in nanny? is this a part-time caregiver?
But generally the amount you pay per week is standard. Along with a handmade token from the children (as they are able).
Child care providers make a median salary of $20,320 per year.
Generally, giving cash to a teacher or a day care provider is seen to be a little uncouth — it seems as though you may be trying to buy better treatment for your kid.
But gift-cards of up to $100 are welcome, as are personal gifts in the area of a provider's hobby or interest.
How much do you tip a dog walker?
Generally a dog walker's tip should be one week's pay.
Devoted dog walkers make a median annual salary of $21,260, although many are part timers or walk dogs in addition to another gig. Dog groomers make about the same amount.
They are likely to appreciate your gratitude for the care they've given your pet at the end of the year.
DogWalker.com, which connects dog owners with walkers, says that one or two weeks pay as an end of year bonus or tip would be greatly appreciated.
Additionally, DogWalker.com says, a gift that has nothing to do with picking up poo, standing in the rain or cold or dealing with drool is thoughtful. A dinner at a nice restaurant maybe, theater tickets or a beautiful teapot.
How much do you tip a barber or hairdresser?
Many clients tip their go-to hairdresser per visit. But if this person has kept you looking your best all year, it is appropriate to give a little something extra at the end of the year.
This also goes for any barber, manicurist or make-up stylist you see on a regular basis.
Typically clients tip the amount of a regular service. So if your regular cut costs $80, you would tip that amount.
How much do you tip a massage therapist or personal trainer?
Personal trainers and massage therapists are paid a little better than the others on this list, but that doesn't mean they don't appreciate a sweet thank you at the end of the year.
Especially if they have hauled you out of bed at the crack of dawn for months and have you in top shape for the holidays.
An adequate year-end tip is the equivalent of a single session.
Of course, if the trainer or therapist have made special arrangements just for you, you have a long standing relationship with them or they come several times a week it is appropriate to tip them more.
How much do you tip a delivery person? Rules of thumb for food, mail and packages
Your UPS driver and Fed Ex delivery person are actually paid fairly well and receive benefits, but if they are lugging your packages around day in and out and you're on a first name basis with them, they should get a tip.
An annual gift of $25 to $50 is appropriate.
United States postal carriers are forbidden from receiving cash or cash equivalents like gift cards at all. They are also forbidden from accepting gifts in excess of $20 from a single customer per occasion, like Christmas.
But within those guidelines a thoughtful gift would surely be appreciated, especially if you see your carrier regularly.
Your newspaper delivery person (who is usually an adult these days), may have placed an envelope in your paper as a reminder for an end of year gift.
At the low end you could give a tip of $10, or you could give an end of year tip between $50 or $60, which would be about $1 tip per week of delivery through the year.