Why do bars put ice in urinals?

You walk into a bar toilet, and the urinal is full of ice. Like a seafood counter, but with worse customers. Nobody tells you why. Nobody ever does. So we went looking.

The honest answer: there isn’t one official reason. There are several plausible ones, mostly told by bartenders and cleaning-industry people rather than measured by anyone. Here they are, roughly from most to least convincing.

1. The ice has to go somewhere

At the end of a night a bar has a bin full of ice it doesn’t need. It can’t go in the sinks, because people need the sinks. It can’t go in the toilets, because someone will flush it and block them. The urinal is the one place left before the back door.

As one explanation quoted by MEL Magazine puts it, that’s simply the only place left. It’s the least romantic answer, which is usually a sign it’s true.

2. It’s a slow flush

Old urinals often didn’t flush automatically, or at all. A bartender at McSorley’s in New York told MEL that the melting ice “acted as a slow, continuous flush”. A urinal full of ice is rinsing itself all evening, for free.

3. It may help with the smell

Several people in the trade say cold ice keeps odours down. One restaurant consultant told MEL that in old buildings smells can rise through the pipes, and “the constant cold drip keeps the odor away”. Others say the cold simply stops the smell rising into the air.

It sounds reasonable. But nobody quoted cites a study, so treat it as experience rather than science.

4. Something to aim at

Give men a target and they will aim at it. That’s the whole idea behind the Schiphol urinal fly. The economist Richard Thaler, who made the fly famous in Nudge, is quoted by CleanLink saying that having something to aim at reduces spillage.

A pile of ice is a target with a bonus: you can watch it melt. One New York bar manager described it to MEL as “kind of a game”. Fewer stray drops, happier cleaners. It’s also the same principle physicists recommend in how to stop urinal splashback: something in the way breaks up the stream before it can bounce back at you.

The stories you’ll read that we can’t confirm

• “Ice kills bacteria and ammonia.” Repeated on lots of websites. We found no evidence for it.
• “It started during Prohibition.” One trade article tells the story of speakeasies hiding surplus ice from the police. No named source backs it up, so it stays a story.
• “Bars started it in the 1960s to amuse customers.” Also told, also unsourced.

Before ice, there were urinal cakes. The early ones were made mostly of naphthalene, the stuff in mothballs, until it was phased out. Ice is cheaper and smells of nothing.

Is ice on the way out?

Probably. Modern urinals flush themselves, and waterless urinals don’t need flushing at all. The founder of a waterless-urinal company told CleanLink that ice is on the way out, if only to save water and energy. He sells waterless urinals, so he would say that. But he’s probably right.

The etiquette

If there’s ice, aim at the ice. It’s there for you. Don’t pick it up, don’t comment on it, and don’t try to carve anything. The man at the next urinal does not want to talk about it either.

All the other unwritten rules still apply, ice or no ice. Read them in The Unwritten Rules, or test yourself in Urinal Rules Forever.