When most people go to a bar, they take care to tip the bartender and/or the wait staff. But for many people, that courtesy seems to go out the window when someone else is picking up the tab, as guests assume that the tip has also been taken care of (or just don’t think about it at all). But are they making the right assumption?

“Every event is unique,” Patrick Maguire, editor of ServerNotServant.com, tells Consumerist, “but as a general rule, guests attending open bar events should always offer to tip bartenders, and many people don’t.”

We also spoke to Zac Hulayev, owner of two bars — the Drake Tavern and the King’s Corner Public House, both in the Philadelphia suburb of Jenkintown — who agrees that there are shades of gray when it comes to tipping at an open bar.

While there are plenty of events — especially weddings and catered business events — where the tip is taken care of, Hulayev adds, “there are the times where hosts will throw a private party with an open bar and the bartenders have tip jars ready to collect the rain of money coming in from guests.”

He says that bartenders at those less-formal events are likely receiving shift pay for their services, so the tip jar is a way for customers who want to show their appreciation by leaving a gratuity. A dollar per drink is a good rule of thumb for those who choose to tip, Hulayev explains.

A small number of event hosts will actually forbid bartenders from accepting tips. Hulayev says that he recently had his money turned away while trying to tip a bartender at an event in Philadelphia. It was a bit awkward, he admits, but at least he knew that the bartender was being properly compensated for the evening.

“The host and the bartender should discuss whether or not tipping will be allowed at the event,” adds Maguire. “If tipping will be allowed, the bartender should furnish a tip jar in plain view, to encourage guests to tip. If drinks are free, you can afford to tip heavy.”

So it seems like the attitude, at least from those who rely on tips for income, is that tipping at an open bar is not mandatory, but that it is definitely appreciated and it will certainly help you get better service.

“Tipping should always be given first priority,” explains Hulayev. “How else are you going to get your much-needed drink in a timely manner without giving the bartender an incentive to remember you?”

This sentiment was confirmed by a bartender at a recent open bar event in New York.

“I’ll survive if someone doesn’t tip me,” she told Consumerist, “but they’ll also survive if I wait to deal with all the tipping customers before I get them their next round.”

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