While tax season is often a stressful time, for retailers, it usually provides a welcome spending boost after the post-holiday lull.

This year, however, some Americans are already reporting dramatically slashed refunds, with some even owing money to the government for the first time in their lives in the wake of President Donald Trump’s federal tax reform bill. According to the IRS, the average tax refund check is down 8 percent, or $170, for the 2018 tax year, compared to the year prior, and the number of people receiving a refund so far has fallen by nearly a quarter.

Using the hashtags #GOPTaxScam and #GOPTaxScamStories, Twitter users have been complaining of unexpected tax bills ranging from around $100 to $10,000 or more. Most said they had expected refunds in line with what they received in prior years, which they planned to put toward everything from tuition payments to child care. (Many also pointed to the recent headlines about Amazon’s $0 federal tax bill as a particular affront, given the circumstances.)

Past years also suggest that a significant number of Americans would likely have spent at least some of their refunds with U.S. retailers, which have come to count on the annual influx of discretionary spending.

As many GOP leaders and conservative lobbying groups have pointed out, the vast majority of Americans did indeed receive a tax cut in 2018, but because of changes in withholding rules, they may have received that money in the form of modest bumps in their weekly paychecks rather than a large lump sum after filing their return. Be that as it may, it’s apparent that many taxpayers haven’t been preparing for a shrunken refund or a bill from the IRS, and eliminating an expected windfall — even just a perceived one — could very well make a dent in retailers’ bottom lines.

The Trump administration’s tax reform bill, passed in December 2017, reduced individual income taxes by an average of about $1,260, according to the independent Tax Policy Center, with high earners seeing the largest cut. But while it raised the standard deduction and raised income limits for child credits, it also got rid of personal exemptions and put new caps on federal deductions for mortgage interest, and for state and local taxes (the latter of which will particularly hit residents of states such as New York, New Jersey and California).

Many families are just learning how all of these changes impact them as they file their returns for the 2018 tax year — and earnings season will tell us whether retailers ultimately feel a ripple effect.