Launched by the Remote Gambling Association in 2017, Gamstop allows players to self-exclude from all online operators who are enrolled in the scheme.
Under the Gambling Commission’s new rule, all online operators will be required to participate in Gamstop by 31 March.
Neil McArthur, CEO of the Gambling Commission, said: “Although the vast majority of operators are already participating in Gamstop, this will make the coverage comprehensive.
“We welcome the fact Gamstop has got to this stage in its development and encourage it to continue to improve its offer, particularly in relation to preventing those who have self-excluded being targeted by direct marketing.
“Operators must do everything they can to minimise the risk of gambling related harm. That is why we expect the industry to create safe products, know their customers, understand what they can afford to gamble with and identify when they are experiencing harm and step in.
“It is also vital people experiencing gambling harm are able to access the support or treatment they need.”
The Gambling Commission has also confirmed a ban on the use of credit cards to gamble, effective from 14 April.