The Triple Block Time Control

Austin Lockwood  Thursday, October 12, 2017

Triple block is an experimental time control introduced by ICCF in 2017; ICCF plan to run some test tournaments to determine how acceptable this time control is to players and organisers.

The time available to a player over the course of a game is allocated in three blocks:

Block 1: The Clock

This is the usual 'clock' we are used to. It is the amount of time a player has available at any given moment during the game. As usual, it counts down one day for every reflection day used.

This is always set at 50 days per player at the beginning of a game, no matter what the scheduled duration of the event.

This is, by analogy, like 'the money in your pocket to spend'. It is what you have to spend that is immediately available to you.

Block 2: The Increment

The second block is called the 'increment'. This is additional reflection time that becomes available automatically after each move made (like a 'paycheck', after earning the new income, it replaces some of what you already spent, with any remaining going into the bank).

The increment replaces the current 'buffer' time that rounds reflection time up to the nearest full day.

The number of days in the increment is exactly determined by the tournament organiser’s decision concerning the length of the event.

The increment is similar to a Fischer clock except for two things:

  • The increment only applies for the first 50 moves of the game, not indefinitely
  • The increment is only added to a player’s clock if the clock has gone below 50 days. A player’s clock cannot be greater than 50 days, ever. Increment time is not lost, however, as any extra goes to the third block, the 'bank' (by analogy: what you do not need to replace in your pocket spending money goes to your savings)

Block 3: The Bank

The bank replaces 'leave time'. There will no longer be any concept called leave time.

Players can 'take leave' any time they wish, but they can never stop their clocks! Players can only replenish their clocks from their banks, until the bank is empty.

Players can even take more than 50 days on a single move, but only by moving time from the bank to the clock within the initial 50 days. If the clock hits zero, the player loses/defaults, no matter what remains in the other two blocks.

Duration of tournaments

Triple block is not intended to speed up play!

Tournament organisers have a great deal of flexibility in setting tournament duration, this can be anthing from 300 days to five years or more.

The advantage of Triple Block is that the total amount of time available to players is determined before the start of the tournament, end dates can be predicted exactly, and adjudications are no longer neccessary except in the case of withdrawals.

Possible future enhancements

One of the concerns raised about Triple Block is the risk of 'sudden death' endings, where a player gets into time trouble after the fiftieth move and no longer recieves any increments; until the test tournaments have been completed, we don't know whether or not these concerns are justified. A possible future enhancement of the system is 'Sudden Death Protection' (SDP), which guarantees a minimum amount of time for each move, however this is not yet implemented and would involve a trade off against the predictability of end dates.

Further details are in the attached document.


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