Gambling companies must pay more to help problem gamblers.
Citizens Advice is calling on the government to require betting companies to pay more towards tackling gambling-related harm, instead of allowing the industry to decide how much they contribute.
According to the Gambling Commission some 430,000 people currently have problems.
In Out of luck, Citizens Advice reports the knock-on effects for families, friends and work colleagues. 4.3 million people may be affected.
More than a third of households with children where there was a problem gambler experienced family breakdown.
Almost one in five people who had a problem gambler in their life said there were times they could not afford food.
More than half of people affected by a problem gambler suffered mental ill-health as a result their behaviour.
In addition to a compulsory levy on gambling companies, Citizens Advice says they should also improve their use of customer information to identify people with problems. More research into local support action is also needed; and more training for staff at banks and creditors on encouraging greater openness.