NEW YORK (AP) — Single mother Rebecca Wood, 45, was already dealing with high medical bills in 2020 when she noticed she was being charged a $2.49 “program fee” each time she loaded money onto her daughter’s school lunch account.

As more schools turn to cashless payment systems, more districts have contracted with processing companies that charge as much as $3.25 or 4% to 5% per transaction, according to a new report from the Consumer Financial Protection Bureau. The report found that though legally schools must offer a fee-free option to pay by cash or check, there’s rarely transparency around it.

“It wouldn’t have been a big deal if I had hundreds of dollars to dump into her account at the beginning of the year,” Wood said. “I didn’t. I was paying as I went, which meant I was paying a fee every time. The $2.50 transaction fee was the price of a lunch. So I’d pay for six lunches, but only get five.”

The U.S. Department of Agriculture, which oversees the federal policy on fee-free school lunch, has mandated that districts inform families of their options since 2017, but even when parents are aware, having to pay by cash or check to avoid fees can be burdensome.

In its review of the 300 largest public school districts in the U.S., the CFPB found that 87% of sampled districts contract with payment processors.

Within those districts, the companies charge an average of $2.37 or 4.4% of the total transaction, each time money is added to a child’s account. For families with lower incomes who can’t afford to load large sums in one go, those fees can hit weekly or even more frequently, increasing costs disproportionately. Families that qualify for free or reduced lunch pay as much as 60 cents per dollar in fees when paying for school lunches electronically, according to the report.

While payment companies maintain that school districts have the chance to negotiate fees and rates when they form their contracts, the CFPB found that complex company structures “may insulate companies from competition and make school districts less likely to negotiate.” Just three companies — MySchoolBucks, SchoolCafe, and LINQ Connect — dominate the market, according to the report.