Correspondence Chess - Deep Thinking Without Time Pressure
With days or even weeks per move, correspondence chess allows the deepest possible analysis and produces some of the highest-quality games ever played.
Published 2026-02-01 | Last verified 2026-02-12
Professor Archer says: Correspondence chess is chess in its purest analytical form. When you have three days to find the best move, there are no excuses. The quality of play is extraordinary.
What Is Correspondence Chess?
Correspondence chess is a format where players have an extended period — typically one to several days — to make each move. Originally played by mail (postal chess), modern correspondence chess is played through dedicated servers and platforms where moves are transmitted electronically.
The extended time allows for exhaustive analysis. Correspondence players can study the position for hours, set up the board at home, consult databases, and in most modern correspondence formats, use engine assistance. The result is chess of extraordinary depth and quality, with far fewer errors than any other format.
Correspondence chess has its own world championship, governed by the International Correspondence Chess Federation (ICCF), and its own rating system separate from FIDE over-the-board ratings.
How Correspondence Chess Works Today
Modern correspondence chess is played on dedicated servers like the ICCF server, Chess.com (daily chess), and Lichess (correspondence mode). Players receive a notification when it is their turn and typically have 1 to 3 days per move, though some events allow longer.
In official ICCF correspondence chess, engine use is permitted. This may surprise players accustomed to over-the-board chess, where engines are strictly forbidden. The rationale is that correspondence chess, with its multi-day thinking times, has always been about the deepest possible analysis, and engines are now part of that process.
However, many casual correspondence platforms and events prohibit engine use, so the rules vary by platform and tournament. Daily chess on Chess.com, for example, does not officially allow engines, and the culture expects human-only play.
A typical correspondence game can last weeks or months. Players often have multiple games running simultaneously, checking in once or twice a day to make their moves across several ongoing games.
Strategy and the Correspondence Mindset
The key difference from over-the-board chess is that there is no time pressure and no excuse for superficial analysis. Every move should be the product of thorough evaluation. This means correspondence chess rewards deep preparation, precise calculation, and rigorous evaluation of alternatives.
Opening preparation is extremely important in correspondence chess. Because players can consult databases and study opening theory between moves, the opening phase tends to follow established theory much deeper than in over-the-board play. Having a well-researched opening repertoire is essential.
Endgame precision is similarly critical. In over-the-board chess, tired players make endgame errors. In correspondence chess, there is no fatigue, so opponents will play endgames with near-perfect accuracy. You must know your endgame theory thoroughly.
The psychological element is different. There is no staring down an opponent across the table, no clock ticking in your ear, no pressure to move. The challenge is purely analytical: can you find the best move with unlimited time? For many players, this pure form of chess is deeply satisfying.
Frequently Asked Questions
Are engines allowed in correspondence chess?
It depends on the format. In official ICCF correspondence chess, engine use is permitted and expected. In casual correspondence or daily chess on platforms like Chess.com, engine use is generally prohibited. Always check the rules of the specific event or platform.
How long does a correspondence game last?
A typical game lasts several weeks to several months. Tournament games with longer time controls can stretch even further. Players usually manage multiple games simultaneously to keep things interesting.
Is correspondence chess good for improvement?
Excellent. The practice of deeply analyzing positions without time pressure builds analytical habits that carry over to faster formats. Many coaches recommend playing at least a few correspondence games to develop patience and thoroughness.
Professor Archer says: I recommend correspondence chess to any student who wants to develop deep analytical habits. The discipline of thoroughly analyzing a position before committing to a move will transform how you think at the board.
Quick Quiz
What is unique about the time structure of correspondence chess?
- Players have days (or longer) per move rather than minutes (Correct) - Correspondence chess gives players one to several days per move, allowing for exhaustive analysis. This is in contrast to blitz (minutes), rapid (tens of minutes), or classical (hours) formats.
- Players have 30 seconds per move - That would be closer to bullet chess. Correspondence chess gives players days per move, not seconds.
- Both players move at the same time - Correspondence chess follows the same turn-based structure as standard chess. One player moves, then the other responds. The difference is in the time allowed per move (days instead of minutes).
- There is a 1-hour total time limit - Correspondence chess has no short-term time limit. Players typically have 1 to 3 days per move, and games can last weeks or months.