If it was me then after oh about 15 seconds max seeing that you made your move and knowing it was then my move I would have gestured. It's the honorable thing to do. I would rather lose fairly than win unjustly.
A question about sportsmanship in chess

I think it is better form not to communicate with the opponent under formal conditions. Less formal conditions I might remind an opponent once or twice. In the end, you're responsible for your clock no less than your moves.
I had a friend who chronically would forget to punch his clock. In our many friendly games I reminded him all the time. After awhile I thought I could help him more by not reminding him at all, prompting his to keep his survival in hand, but it seemed to make no difference. I just ended up with more time for my game, and he with less for his.
It was a bit unfair for me to be burdened with managing his time. In a tournament I shouldn't be taking my opponent's time-issues on my back when they shoud be on his alone.

It is good sportmanship to remind your opponent to hit their clock, but you do not HAVE TO remind them.

I usually tell my opponent, even in a serious match, but only after giving them a little time to make sure they aren't realizing their mistake.

It is good sportmanship to remind your opponent to hit their clock, but you do not HAVE TO remind them.
If you HAD TO do it, it wouldn't be a question of sportsmanship. But what respectable reason is there NOT to give the little reminder, at least once? Saying that it's "better form" not to communicate is not saying anything.
It probably is "right" to tell them not to press the clock, but internally laughing at them is more fun. In most of the games I play, one side running out of time is usually a symptom of the other side's good play so I doubt that this will change the result, just let people go home earlier.

It is good sportmanship to remind your opponent to hit their clock, but you do not HAVE TO remind them.
If you HAD TO do it, it wouldn't be a question of sportsmanship. But what respectable reason is there NOT to give the little reminder, at least once? Saying that it's "better form" not to communicate is not saying anything.
It's following the rules. That's what is meant by "better form" and "formal."

Also, if this is happening under tournament conditions, if you feel compelled to inform your opponent about his clock, go tell an arbiter or td so he can pass along this information. He'll probably tell you he'll do nothing of the kind but give it a shot.

Are you there to win or make friends? If its the former don't remind them..if the latter go ahead and remind them..Personally i play to win, under any conditions possible..my last tournament win was on timeout on the last game where i was being ripped apart by my opponent..i took a full 2 minutes on my last move on her time to get my win and the prize..its legal so why not use it?
Last night I played at the local club. Deep into the middlegame I forgot to hit the clock after a move, and 10 minutes or so elapsed while my opponent happily pondered his move on my time. He was down on time, so it actually mattered. After the game, I asked why he didn't remind me to hit the clock (as others have done). He said that opponents are "under no obligation" to help each other, and in fact "should not" communicate at all during a game.
What do you think? Would you be happy to win a game because your absent-minded opponent (perhaps fairly new to rated chess, as am I) didn't hit the clock? Especially in a club setting, I think chess players should avoid taking unfair advantage. Granted, I should try to avoid making that mistake, and it would be really annoying if you had to keep reminding someone to clock. But ten minutes is ridiculous.
Please don't say it's my mistake; I know that. I just want to know if you would do the same thing he did, or if you would have quietly gestured at the clock.
I am sorry, banjoman, but at OTB competition it's your responsibility. So don't blame other player for your oversight. It'll also make you unsportsmanlike. The more you play at those events, you will develop a routine (body movement), and you will not make this error again....

Yeah, gosh, well... I didn't blame him for my mistake. Try reading that part that you quoted again so that you can understand this discussion. The question is, what would you do, and why.
I appreciate the honesty of the guy who says he just wants to win by any means. But I have no respect for people like that. The point is to win AT CHESS, where you and your opponent have equal amounts of time.
no, the point is you forgot to hit the clock and you tried to blame it on unsportsmanlikeship....lol
I was right, you are a crywhimp.

no, the point is you forgot to hit the clock and you tried to blame it on unsportsmanlikeship....lol
I was right, you are a crywhimp.
You are very clearly not bothering to read the thread.
The OP said very clearly that it was their mistake, and they took responsibility for the mistake. The post went to on explain that they personally would have reminded their opponent to hit the clock, and asked for what other's would do in a similar situation.
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On-topic, I would probably wait about a minute or so, and then let my opponent know.

I'll remind someone two or three times in a game, but if they're chronic about it I'm not going to waste my time managing their clock. I'd do the same in a tournament game. If the TD has a problem with it, then the TD has a problem.

spoiler, he admitted it was his fault and there was no obligation on his opponent to inform him. He was just asking what the people here would have done. For me it depends, how serious is the game? Do I know or like the opponent? To me there is no agreed rule of sportsmanship. If it was a team league or tournament match I would not most likely point it out unless I knew the person, even then I would let it run for a bit first. In the past I have often not brought it to my opponents attention, but once I had decided on my move I wouldn't just sit there and let his clock run out. (I'm not a total monster)
Banjoman, if it wasn't a club tourney I certainly would have pointed it out much earlier, but he has taught you a valuable lesson. On rereading I see you mention it was a rated game...if he was down on time, I would have no issue and I certainly wouldn't have asked him why he hadn't tipped me off.

all games and sports have rules.mistakes cost so learn the hard way.i have and looked at my self not my oposition

I just move normaly and tap my button on the clock as if my opponet had hit there's
Isn't it illegal to move your pieces on your opponent's clock?

I just move normaly and tap my button on the clock as if my opponet had hit there's
Isn't it illegal to move your pieces on your opponent's clock?
Most games I play with a clock are informal with my friends. In a tournament or formal setting I devise my move normaly and then tell my opponet about their clock.
Last night I played at the local club. Deep into the middlegame I forgot to hit the clock after a move, and 10 minutes or so elapsed while my opponent happily pondered his move on my time. He was down on time, so it actually mattered. After the game, I asked why he didn't remind me to hit the clock (as others have done). He said that opponents are "under no obligation" to help each other, and in fact "should not" communicate at all during a game.
What do you think? Would you be happy to win a game because your absent-minded opponent (perhaps fairly new to rated chess, as am I) didn't hit the clock? Especially in a club setting, I think chess players should avoid taking unfair advantage. Granted, I should try to avoid making that mistake, and it would be really annoying if you had to keep reminding someone to clock. But ten minutes is ridiculous.
Please don't say it's my mistake; I know that. I just want to know if you would do the same thing he did, or if you would have quietly gestured at the clock.