Gambling operators who breach regulations are to face higher penalties and a greater chance that their licence will be reviewed under a new enforcement strategy unveiled by the regulator.
The Gambling Commission said it would use the "full range of enforcement powers to ensure operators put customers first and raise standards" under the strategy, which comes into force today.
Among the changes are higher penalties for regulation breaches, particularly when they are systemic and repeated, and placing the option of licence review on an equal footing by removing the current bias towards settlement.
Gambling Commission chief executive Sarah Harrison said: "We will use the full range of enforcement powers to ensure operators put customers first and raise standards.
"The industry can be assured that we will use our powers in a targeted way, and consumers and the public can be assured we will take robust and effective action when gambling companies don't meet their obligations."
She added: "This enforcement policy will set tougher sanctions for operators who repeatedly or systemically fail their customers.
"We want to work with operators who want to raise standards, we will take tough action against those who fail customers. Operators who persistently fail customers will face a hostile response from the regulator."
Brian Chappell, founder of the campaign group Justice4Punters, said: "We are delighted by this announcement.
"It confirms the discussions in our meetings with the Gambling Commission that they are committed to improving customer service for gamblers.
"Gamblers really struggle to get any justice at all from companies and any regulatory changes that help with this situation are very welcome."
The new strategy comes days after the competition watchdog announced it is to take enforcement action against online gambling companies suspected of breaking consumer law.
The Competition and Markets Authority (CMA) said it was taking the action because punters were not getting the deal they expected from sign-up promotions, and some operators were "unfairly holding on to people's money".
Sign-up promotions are designed to attract players onto casino-like gaming websites by offering bonus cash when they put in their own money.
It followed a joint programme with the Gambling Commission and comes amid concerns that promotions offered by some online bookies come with terms and conditions that are often "confusing and unclear and, in some cases, may be unfair".
In March, the Gambling Commission said the industry's system for handling complaints was "not working" for consumers, who had raised questions over its independence and transparency.
Consumers found the complaints process difficult to access and time-consuming to use and there was "a clear need" for both gambling businesses and alternative dispute resolution (ADR) providers to improve their handling of disputes, the regulator said.