Gambling websites could introduce a £100 loss limit to protect lower-income customers under plans being considered by ministers.
New industry-wide "affordability checks" should be introduced to identify vulnerable gamblers, according to a report by think tank the Social Market Foundation.
It proposes a "soft cap" on spending under which anybody wanting to spend more than £23 a week on gambling would automatically be asked to demonstrate that they could afford to lose the money without hardship.
The checks could come in the form of asking people to provide their credit rating, pay slips or tax returns, the think tank said as it argued for "protective regulation" of the industry. If someone showed they could afford to gamble the money, they would be allowed to do so.
The cap would not be applied to a situation in which someone won money and wanted to use the winnings to place another bet. At present, operators conduct their own affordability checks if they think a customer may be at risk.
Under the proposals, an ombudsman would have access to data from all operators and oversee a new process of standardised affordability checks.
The think tank's report was this week presented to ministers in the Department for Digital, Culture, Media and Sport and the Department of Health and Social Care, as well as Number 10's policy unit.
It comes ahead of a major Government review of the UK's gambling laws, expected in the autumn.
James Noyes, the author of the report, said: "For too long, gambling operators have talked about the need to protect their customers, but have not worked together in order to make affordability checks a reality.
"A fixed cap that applies across operators is the only way that consumers can be protected from harmful spend."
Mr Noyes, a former adviser to Tom Watson, said the proposed threshold "sets the bar low enough to protect everyone, including those on low incomes, but is high enough to reflect the vast majority of gambling activity among the general population".
He added: "Gamblers should be free to spend more than this threshold – but only after they show that their gambling is neither unaffordable nor harmful."
The report also proposes other reforms to the gambling industry, including changes to the way it is taxed and limiting online slot games of up to £5.
Companies should also have a "minimum footprint" in the UK as a way of curbing companies operating primarily offshore, it says. The document argues for a system of incentives, such as tax rebates, for those companies with a sufficient base in the UK.
A clearer system of sanctions should be introduced in line with those used by City regulator the Financial Conduct Authority, the report says.
Gambling industry body the Betting and Gaming Council, said: "We already carry out robust and improved affordability checks.
"We disagree with the suggestion of an arbitrary and random low cap on spending and can think of no other area of the economy where the Government determines how much an individual can spend."