Shut the Box

Overview

Roll two dice and close numbered flaps matching the total. Close them all and you have shut the box. A traditional pub game with more mathematics in it than it looks.

No governing body publishes rules for this game. This page describes the most common form. House rules vary, so agree them before you start.

1. Setup

A wooden box with flaps numbered 1 to 9, all standing open. Two dice.

Some boxes go to 10 or 12.

2. A turn

1. Roll both dice.
2. Close any combination of open flaps summing to the total rolled.
3. Roll again and repeat.

A roll of 8 lets you close 8, or 5 and 3, or 6 and 2, or 1, 3 and 4 — whichever combination of open flaps you prefer.

Your turn ends when you cannot make the total from the flaps still open.

3. The one-die rule

Once the flaps numbered 7, 8 and 9 are all closed, you may choose to roll one die instead of two.

With only low flaps left, two dice often overshoot, so this matters. Not every table plays it, so agree first.

4. Scoring

Your score is the sum of the flaps still open when your turn ends.

Lowest score wins, so a score of zero — shutting the box — is unbeatable.

5. Strategy

There genuinely is some.

Close the high flaps first. A 9 can only be made by a 9, or by combinations that use up several small flaps. Leaving it open late is how turns end.

Prefer one flap to two where you can, early on — but reverse this late, because having several small flaps gives you more combinations.

Get to the one-die rule. Clearing 7, 8 and 9 lets you roll one die for the small totals you need.

With perfect play on a nine-flap box, using the one-die rule, you shut the box about 1 time in 10. That is our own calculation of every possible sequence of rolls.

Commonly argued

• You may close any combination summing to the roll, not just a single flap.
• The one-die rule applies once 7, 8 and 9 are down, where it's played.
• Lowest score wins, which catches people who assume higher is better.
• Nine-flap boxes are the most common. Bigger boxes change the odds.