Round Time has appeared in every Worms game (except for the spin-offs). It is shown in the bottom left corner (or in the bottom right corner in newer games), just below the Turn Time. It is the amount of time left before Sudden Death is activated. It is important to keep an eye on the Round Time, because if the Round Time expires and the round is still not over yet, Sudden Death will be activated and will either cause the water level to rise, drain every Worm's health to 1 health point (or both), or trigger a Nuke. It may also end the round completely, regardless of who is in the lead. Round Time display can be toggled on or off (leaving it on is recommended) when editing or creating a Scheme. Each Scheme also has different amounts of different amounts of Round Time, and you can also toggle the amount of Round Time during a round when editing or creating a Scheme. The available options are:
- 00:00 Minutes (This will activate Sudden Death right when the battle begins.)
- 05:00 Minutes
- 10:00 Minutes
- 15:00 Minutes
- 20:00 Minutes
- 25:00 Minutes
- 30:00 Minutes
- In some Worms games, such as Worms Armageddon, the Round Time numbers turn red when the Round Time expires, indicating that Sudden Death is imminent.
- In some Campaign Missions of some Worms games, the Round Time is even higher than 30 minutes, usually 45 minutes.
- The Story Mission "Nice To Siege You" from Worms 4: Mayhem and Worms: Ultimate Mayhem is currently the only mission in the series where the Round Time must expire in order to win.
- In some games, if the Round Time is set to 00:00 in the game settings, the Round Time will start counting up once the battle begins instead of counting down, to show the total game time that has passed for that round.
- In some games, such as Worms Armageddon, the Round Time only counts down during turns and sometimes stops counting down, usually in-between turns. However, in other games, such as Worms 4: Mayhem, the Round Time never stops counting down until it reaches 00:00.