Half a million renters could lose their home without financial help, debt charities, lenders and landlords have warned.
These renters are under pressure from debt they've built up since the pandemic.
A group of organisations has asked the government for a targeted support package to help struggling people.
A spokesperson said the government had put in place schemes to support households.
The group of organisations warned of renters losing their homes in the coming months, and a rise in homelessness, without more support.
"The longer the Chancellor waits to take action, the more rent debts will increase," the organisations said.
They pointed to government research from July on English housing which found that "private renters report being hardest hit by the pandemic".
Last month Citizens Advice estimated that at least half a million private renters are in arrears because of the impact of Covid-19.
And earlier this week the Resolution Foundation said that more than 750,000 had fallen behind on housing costs in January. That was 450,000 more than a year earlier.
The think tank reported that just 3% of private renting families have been able to negotiate a lower rent over the last 10 months.
The call for action came from the Big Issue Ride Out Recession Alliance, Crisis, Citizens Advice, the Joseph Rowntree Foundation, the Money Advice Trust, the Mortgage Works, the National Residential Landlords Association, Nationwide building society, Propertymark, StepChange Debt Charity and Shelter.
The organisations called on the Chancellor Rishi Sunak to introduce help for renters in his forthcoming Budget, which is set to be announced on 3 March.
They asked for a targeted financial package to help renters pay off arrears built up since lockdown measures started in March last year.
They said it's needed to help to sustain existing tenancies and keep renters in their homes while also ensuring rental debt does not risk their finding homes in the future.
They said renters need to know that they can afford their homes by having a fairer welfare system.
"The government increased Universal Credit and Housing Benefit because it recognised that the system was not doing enough to support people in the first place, yet it has chosen to freeze Housing Benefit rates again from April and is considering cutting Universal Credit at the same time.
"It cannot be right that these measures could be pulled away from renters during continued economic uncertainty," they said.
"We urge the Chancellor to act now to avoid renters being scarred by debts they have no hope of clearing and a wave of people having to leave their homes in the weeks and months to come," they added.
A government spokesperson said: "We've put households at the heart of our decision-making throughout the pandemic, with a £280bn package keeping millions in work, temporarily bolstering the welfare safety net by more than £1,000 a year for families, and backing businesses with loans and grants.
"We're supporting renters by extending notice periods and banning bailiff enforcement of evictions for all but the most serious cases. Councils can also provide additional help through the £180m discretionary housing scheme."
Support for renters
On Sunday, housing secretary Robert Jenrick announced that a ban on bailiff-enforced evictions in England would be extended until 31 March.
The ban was introduced around the start of the pandemic to protect private renters and will remain in place for all but the most serious cases.
Mr Jenrick said: "We have taken unprecedented action to support renters during the pandemic."