Is It Rude to Specify End Times for Parties?

Dear Helena,
I am planning a small drinks party and am concerned that some of my guests will not leave until after midnight. Is it rude or at least nonfestive for me to specify an ending time, such as 12 a.m., on the invitation? I don't want my guests to feel like I'm booting them out the door.
—Early to Bed

Dear Early to Bed,
I sympathize with your desire not to have your drinks party turn into an all-night rager. Before I had a baby, I loved that kind of party, and my guests never left before 2 a.m. But nowadays, like you, I'd rather not stay up past midnight. And there's nothing rude about making this clear on the invitation. It's certainly better than interrupting a party in full swing by switching off the music, distributing coats, and yelling, "Who needs me to call them a cab?"

When you're throwing a dinner party, there's no need to specify a departure time, because dinner gives the evening a natural beginning, middle, and end. Everyone knows that dessert is the signal that things are winding down (unless you break out the liqueurs and suggest a game of charades). But a drinks party is different, because there is no social consensus on how long it should last. People with kids probably want to be home by 11 to relieve the baby-sitter, and middle-aged guests often fade by midnight. But twentysomethings might be happy to hang out until dawn.

Specifying an end time on the invitation does more than just tell guests when you want them to leave. It also tells guests (or at least polite ones) when you want them to arrive. Showing up as much as an hour late to a party that has an open end time is common practice in New York, says museum consultant Cate Conmy, and, she says, every guest has a ready-made excuse: the subway. In her view, the problem is that guests see parties as being akin to concerts. "If you're going to see a band, it never really starts at the designated time, but maybe an hour or more later."

If you set an end time, guests will stop treating your drinks party like a concert where they can drift in whenever. Instead, they'll treat it like a movie, where they won't show up late because it means missing too much.

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