Call it the most debt-filled time of the year.

Not every shopper budgets for the biggest shopping holiday. As a result, many consumers took on debt during this holiday season. More than 65% of those who took on debt did so unexpectedly, according to a survey from the personal finance company MagnifyMoney. The company used Google Surveys to find a nationally-representative sample of more than 550 who said they took on debt this holiday season.

They took on $1,003 worth of holiday debt on average, up from $986 in 2015, a 1.7% increase, MagnifyMoney found, and about half of those surveyed said they will be paying off their debt for four months or more. Although spending can be seen as an indicator of higher consumer confidence in the economy, taking on holiday debt still isn’t a good thing, said Nick Clements, the co-founder of the company.

Roughly one-third of retail sales take place during the holidays, according to the National Retail Federation, the industry group representing retailers. Holiday shoppers came out in droves this year: 154 million people planned to shop during Thanksgiving weekend, up from 151 million in 2015, the NRF said. The biggest holiday shopping day was Dec. 17, when 156 million people shopped.

The NRF expects sales in all of November and December — excluding autos, gas and restaurant sales — to hit $655.8 billion this year, including non-store sales of $105 billion, up 3.6% on last year. What’s more, Black Friday and Thanksgiving online shopping surpasses $5 billion for the first time this year, according to estimates from software company Adobe Digital Index.

Some forms of debt, including mortgages, indicate hope for the future, but Clements is “less optimistic about excessive borrowing on credit cards,” he said, calling it “a bad habit.” Nearly 60% of those MagnifyMoney surveyed said they put their holiday debt on credit cards. And they’re not alone: American households with credit card debt have an average of $16,061, up from $14,546 10 years ago, according to the Federal Reserve Bank of New York.

“It’s so easy to spend an extra $5, $10 or $20 when you’re just swiping,” Clements said. Case in point: Paying interest on credit-card debt can put individuals in financial trouble, such as this family who racked up $89,000 on 11 credit cards and had to take on additional jobs and slash their spending as a result.

For those who want to get their spending under control, during the holidays or any other time of year, Clements suggested going on an all-cash spending diet. Although those using only cash would miss out on credit-card rewards, tracking spending this way “forces you to pay attention,” Clements said. “You’re so much more careful.” Consumers should also force themselves to read their credit-card statements, instead of ignoring them because of regret and anxiety, he added. They should also check their credit scores and try to improve them in the New Year by paying bills on time and considering refinancing debt, he said.