Two of them - stalemate and insufficient material - take effect automatically: the game is over the moment they occur. The others have to be claimed, and that distinction matters at a tournament.
The side to move has no legal move available, yet its king is not attacked. The game ends immediately in a draw - regardless of material.
This is the most painful rule for beginners: a player with an extra queen takes away every square from the enemy king, forgets to give check, and half a point evaporates.
How to avoid it
Before every queen move in a won position, check that the enemy king still has at least one square. If it has none and you are not giving check, that is stalemate - the technique of the basic mates.
From the other side, stalemate is a defensive resource: in a hopeless position it is often the only thing to play for, and studies are full of it.
Some material simply cannot force mate, so the game is drawn the moment it arises. The combinations are:
Two knights against a lone king are a special case: mate is theoretically possible but cannot be forced, so play normally continues until the fifty-move rule settles it.
The practical lesson for the endgame: when simplifying with a material edge, do not end up with a single minor piece. An extra pawn is worth more than an extra bishop in that situation.
If the same position occurs three times, a draw may be claimed. Three conditions have to match, and people forget them:
The repetitions do not have to be consecutive: positions occurring at different points in the game count too. In practice the claim usually comes from perpetual check, where the same position returns every two moves.
Important: this is a right, not an automatic result. If nobody claims, the game continues.
If fifty consecutive moves by each side pass with no capture and no pawn move, either player may claim a draw.
The logic is simple: if nothing has changed irreversibly in fifty moves, neither side is making progress. Any capture or pawn move resets the count to zero.
In practice the rule matters in technical endgames - bishop and knight against a king, or rook and bishop against rook - where the winning method runs long and the count becomes a real constraint. It also has to be claimed, and at an event with notation the players track it from their own scoresheets.
A series of checks from which the king cannot escape. Formally there is no separate «perpetual check» rule - the draw arrives through threefold repetition - but every player uses the term.
It is the most common practical saving resource: a player who is losing gives check after check, the position repeats, and the game ends level. Which is why in a winning position it is worth spending a move to remove the possibility of endless checks before it appears.
The players may agree at any moment. The correct procedure: make your move, then offer the draw, then press the clock. Offering before moving hands your opponent extra information for free.
For repetition and the fifty-move rule the procedure is formal, and getting it wrong costs you the claim:
Which is another reason to keep an accurate scoresheet: without it a repetition claim cannot be verified - other formal situations.
A draw gives each player half a point. That is simple; what is less obvious is how it affects the table.
The side to move has no legal move but its king is not in check. The game is drawn immediately, regardless of material. It is the most common way beginners throw away a won position: an extra queen takes away every square without giving check.
King against king, king and bishop against king, king and knight against king, and king and bishop against king and bishop of the same colour. Two knights against a lone king are an exception: mate is possible but cannot be forced, so the game continues.
If the same position occurs three times - with the same side to move, the same pieces on the same squares and the same rights, including castling - a draw may be claimed. The repetitions need not be consecutive, and the draw is not automatic: somebody has to claim it.
If fifty consecutive moves pass with no capture and no pawn move, either side may claim a draw. Any capture or pawn move resets the count. It matters mainly in long technical endgames, and it too must be claimed.
Make your move first, then offer the draw, then press the clock. Offer only once - repeated offers count as distraction. An offer cannot be withdrawn, and silence is not acceptance: the reply is either a word or a move, and a move means refusal.
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Rules - etiquette, lateness and forfeits, basic checkmates, glossary.