Debt charities expect to have one of their busiest Januarys in years, as consumers recover from the Christmas spending period.
Citizens Advice said it expected more than 370,000 people to seek advice on money matters during the month.
Meanwhile, the Money Advice Trust (MAT) said more than five million people could run into financial difficulties.
The MAT said its National Debtline service had already had its busiest December in four years.
It took an average of 715 calls a day over the four weeks, and helped more than 40,000 people online.
Looking ahead, the MAT said “perilously few” people have set a budget, or have a plan to repay existing debts.
Just before Christmas, the governor of the Bank of England, Mark Carney, warned about the high level of debt among UK households.
Unsecured debt, including spending on credit cards, is rising at its fastest pace in 11 years, the Bank of England said.
An online poll, conducted for the MAT by YouGov, suggested that 11% of consumers expect to fall behind with their finances in the New Year, equating to around 5.5 million people.
About 32% have set a budget they plan to stick to, and 12% have a strategy to repay debts they already owe, according to the poll of 2,000 people.
“January can be a difficult month for household budgets – and it is easy to see how many people fall behind when the bills for Christmas spending begin to land,” said Joanna Elson, the chief executive of the MAT.
“Unfortunately our research shows that perilously few households have a plan for how to repay the debts they currently owe – and many could fall into serious difficulty as a result.”
Citizens Advice said it expected a call for financial advice every three seconds in January.
While many people worry about personal debt, it said many others want help with planning long-term finances.
“Although debt worries can be more acute in January, people are also taking stock of their finances and thinking about the future,” said Gillian Guy, the chief executive of Citizens Advice.
“It doesn’t matter what your earn – whether you are on minimum wage or have a comfortable salary – everyone can benefit from reviewing their finances.”
As part of its advice, National Debtline recommends that consumers:
- Set a budget for 2017
- Open all their statements, and act on them
- Seek free advice where necessary
Last week, a survey for Uswitch suggested that consumers would carry an average outstanding sum of £636 on their credit cards into the New Year.