Short answer: in standard 501 or 301 darts, you cannot go past zero and win. If your score goes below zero, you bust. Your score goes back to what it was at the start of that visit, and your turn ends. You also bust if you reach zero in the wrong way under double-out rules.
Last checked: 26 June 2026. This guide assumes common steel-tip 501 or 301 rules. Pub, league and soft-tip formats can vary, so confirm the house rules before playing.
What “bust” means
A bust is a failed visit when your darts leave you below zero, on an impossible remaining score, or on zero without satisfying the finish rule. In most standard double-out games, you must finish exactly on zero with a double. If you overshoot, your score does not partly count. The whole visit is cancelled and you return to the score you had before you threw the first dart of that turn.
For example, if you have 32 left and hit single 20, you have 12 left. If your next dart hits treble 20, you have scored too many. The visit is bust, your score returns to 32, and your opponent gets the next turn.
Common bust examples
| Score left | Dart thrown | Result |
|---|---|---|
| 40 | D20 | Game shot |
| 40 | S20, S20 | Zero without double: bust in double-out |
| 32 | T20 | Too many: bust |
| 2 | S1 | Leaves 1: bust in double-out |
| 25 | Outer bull | Zero without double: bust in double-out |
Why reaching exactly zero is not always enough
Many beginner mistakes happen because players think zero is the only target. In double-out darts, the final dart must land in a double segment or the inner bull, which counts as 50 and is normally treated as a double bull. If you reach zero with a single, treble or outer bull, you have not finished correctly.
That is why 40 is a strong finish: double 20 wins. 32 is strong because double 16 wins. 25 is awkward because the outer bull scores 25 but is not a double-out finish in standard rules. If you have 25 left, you usually need to set up a double rather than simply hit 25.
What happens to the darts already thrown?
They do not count for that visit once you bust. This is important. If you start on 40, hit single 20, then bust with the next dart, you do not stay on 20. You return to 40. The bust cancels the whole turn, not just the final dart.
This rule creates pressure because a risky dart can waste a good setup. It also rewards players who know safe routes and avoid leaving awkward numbers.
Why leaving 1 is a bust
In double-out, you cannot finish from 1 because there is no half-point double. If a dart leaves you on 1, the visit is bust. This catches players on double 1. If you have 2 left and hit single 1, you have not simply left yourself 1 for later. You have bust and return to 2.
This is one reason players try to avoid the “madhouse” of double 1. It is not physically smaller than other doubles, but the recovery options are poor.
Checkout planning prevents busts
Busts often come from poor planning rather than bad aim alone. If you have 62 left with three darts, you should know the route before you throw. If you have 41 left, you should know whether you prefer single 9 for double 16 or single 1 for tops. If you make the maths up while your arm is already moving, your chance of a careless bust rises.
Beginner-friendly finishing routes
- 40 left: aim D20.
- 32 left: aim D16.
- 24 left: aim D12.
- 16 left: aim D8.
- 10 left: aim D5, or use S2 to leave D4 if you prefer.
- 6 left: aim D3, or use S2 to leave D2 depending on comfort.
These are not the only routes, but they show the principle: know your preferred doubles and work backwards from them.
How to practise avoiding busts
Start from 61 and give yourself three darts to leave or hit a clean double. If you bust, reset to 61. Then repeat from 62, 63 and 64. This teaches you to think through the first dart and understand what each miss leaves.
Another useful game is “no bust finishing”. Start from 40, 32, 24 and 16. Your goal is not only to finish, but to avoid careless singles that leave impossible numbers. Track how often you get a dart at a double without busting.
Equipment note
A clear board and consistent darts make finishing practice easier to judge. If your doubles are worn or bounce-outs are common, checkout practice becomes misleading. For a reliable practice setup, browse dartboards, dart sets and darts accessories.
Bottom line
You cannot go past zero in standard darts. You must reach exactly zero, and in double-out formats the final dart must be a double or bull. Busting is part of the game, but repeated busts usually mean you need better checkout planning, calmer target choice and more practice on common doubles.
FAQ
Do you lose the whole turn if you bust?
Yes. Your score returns to what it was at the start of that visit.
Can you finish on a single?
Not in standard double-out darts. Some casual formats may use different rules.
Why is leaving 1 a bust?
Because there is no double that scores 1.
Can bull finish a leg?
Yes, the inner bull scores 50 and can be used as a finishing double in standard rules.
