Tipping hotel housekeeping is one of the customs that everyone is supposed to do, but most people forget. Perhaps you’re running late to catch a plane or don’t know the appropriate amount to leave. No matter the reason, less than 30 percent of hotel guests leave a tip, according to the American Hotel & Lodging Association. That low number may not seem like a big deal to you, but for the people who make your bed, pick up your socks off the floor, and empty your garbage, it matters. The median hourly wage for a hotel housekeeper in the United States is just over $9, according to PayScale, and tips can add another 10 to 20 percent to take-home earnings. Below, we answered some of the most common questions around tipping hotel housekeeping.

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When should you tip?

Timing may be the biggest topic up for debate when it comes to tipping hotel housekeepers. While many guests put aside money for housekeeping just before checkout, tipping every day may be more beneficial to both you and the staff. The housekeeper for a hotel room often changes daily, so if you only splurge on the last day, you may be giving one person a nice bonus and unintentionally stiffing others who made up the room, explains Sheryl Hill, Executive Director of Depart Smart. Hill leaves a small amount in an envelope on the dresser each day and she occasionally receives thank you notes in response. “I’ve noticed that there might be an extra mint on the pillow, or an extra bottle of water on the nightstand, if you tip during your stay versus waiting until checkout,” explains Hill.

How much should you tip?

Most people know to leave at least a 15 percent tip for restaurant servers. The amount you should leave for hotel housekeepers, however, isn’t common knowledge. The American standard is $2 to $5 per day, says Rick Camac, Dean of Restaurant & Hospitality Management at the Institute of Culinary Education. That said, you can definitely drop more, if you’d like.

How should you tip around the world?

Research local tipping customs before placing any dollars on the nightstand. In some locations, particularly in Asia, the extra money can be an unintentional slight. For example, in Japan, be mindful of the hospitality tradition of omotenashi. “It’s the belief that the comfort of your guests is of the utmost importance, so that they have the best experience,” says Kenny Colvin of Giant Squid Creative. “The Japanese think tipping is insulting because they wouldn’t give you any different service than they would give anyone else, so they shouldn’t be tipped for it.” Camac remembers that he once tried to give a housekeeper in Chiang Mai a $20 bill. “He looked at me like I had three heads,” he said.

If you’re in Europe, South America, or the Middle East, tips for hotel housekeeping should be comparable to or a little less than the U.S., depending on the country. Unsure what the local expectations are? Tip at least $2 and you should be in the clear.

Should you tip extra for good service?

Most guests probably won’t need a hotel housekeeper to deliver a razor or shampoo, but for those who do, it’s good to have a sense of protocol. Camac says he usually keeps a couple of dollars handy every time a staff member runs up to his room for an extra request, like a travel toothbrush. However, he draws the line at paying extra for something that’s supposed to be in the room (like an expected amount of towels in the bathroom).

Hill was happy to reward an Australian hotel housekeeper who helped her out in an unexpected way: “I left my PC charger on the airplane. She brought me a replacement to keep, because she said they had many. I asked for her name and wrote a rave review and left a big tip. She saved the day.”

Where should you leave the tip?

While you may think it’s obvious that any money left on the dresser is meant for hotel housekeeping, you can bet that guests have accidentally left cash behind and then accused staff of stealing it. Leave the cash in an envelope on the dresser or desk along with a quick note that reads “thank you housekeeping,” advises Devoreaux Walton of the etiquette site The Modern Lady.

How much should you tip if you leave behind a big mess?

You don’t need to be a rock star to trash a hotel room. Plenty of guests do it all the time. And who has to clean up afterwards? Hotel housekeeping. One time after a wedding, Camac invited several people from the reception back to his hotel room for a soiree that ended around 4 a.m. The next morning, he had to catch a flight. “I woke up and there was no time to clean up anything,” he recalls. “There were glasses everywhere. I felt bad, put 50 dollars on the dresser, and ran out of there.”

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