Do I have to say check in chess?
When you play against a computer, it doesn’t allow you to play any move when you are in check unless it evades the check.
On the contrary, announcing checks is not required in the FIDE Laws of Chess. It specifies that there is no obligation to say the word check after attacking.
Saying check after an attack on an opponent’s king used to be required but was abandoned in the early 20th century.
Before that, chess players were so nice that they would even say garde to alert an opponent that his queen was being attacked.
Because saying the check isn’t required, your opponent can all an arbiter for verbal disturbance when you check him or her frequently. Although it is not prohibited in friendly games, it is still not compulsory to say it, nor is it an abandonment of politeness.
It could even be considered demeaning, given that there are only two players in a game over the chessboard. Given that the check is an important forced move that may occur, both players are supposed to be paying close attention to what’s going on immediately in front of their eyes.
Nonetheless, players of all skill levels frequently fail to detect they are in check, you can get engrossed in thought of prospective future moves. In a rated competition, if a player makes an illegal move rather than resolving a check and then punches the clock, the opponent may instantly click his clock button to continue the player’s time and then remind him that he is on a check.
The illegally moved or touched piece would be forced to intervene with the check. If this is not possible, there is no penalty, but any move that relieves the check must be made before the player can punch the clock again.
If you were just playing with your friends and families, it is better to set the rules first about saying check, only then can there be guidelines to follow if regulations are violated.
Because rules are always nice to have even if you are just playing friendly games, so, if you were to play with a much standard chess game, then you already have a basic foundation of following tournament type rules. If you have any doubts about the rules, you can contact the arbiter for clarity.
It is good practice to consider that your opponent may not say check. It means any time you are under considerable attack, you will be looking very closely at the last move your opponent made. Making a double check is something you should get into the habit of doing for every single move an opponent makes. This is because there is a penalty for playing an illegal move and you can even lose the game!
What is going to happen in a chess game when you don’t say check?
Do I have to say check in chess?
Since the answer to the question do I have to say check in chess is no. Then it’s nothing, there are no official rules in the laws of chess saying otherwise, and there is no obligation to say check in chess when directly attacking an opponent’s king. It is up to your opponent to notice the position and avoid the check or make an illegal move which could lose them the game.
In games at the highest level, this would happen maybe once in a lifetime. No top-level chess player will be getting into a position where a check is possible from the opponent, let alone missed when it does happen, regardless of warning or not.
Do you say Checkmate?
Again, there is no rule in the laws of chess that dictate that a checkmate should be said.
At some level, it might be taken as offensive to have your victor rub salt in the wounds with an outspoken checkmate when it lands. It is rare to see a checkmate at the highest level of chess anyway.
So, if you are playing a real competition, or a semi-competitive round chess game, do not say check, when playing casual games with family or friends or at a beginner level over the chessboard, do what you both agree on. When teaching someone chess, definitely point the occurrence out, but also explain to them this ‘non-rule’ so that they know early on in their learning.
Check out Can You Checkmate With Two Knights?