Your refund depends on what you withheld, not on the tax year itself

Whether your refund grows or shrinks has almost nothing to do with the calendar. It depends on how much money your employer took out of your paychecks during the year, compared to what you actually owed. If you had more withheld than you owed, you get a refund. If you had less withheld, you owe money. The size of that refund or bill is the difference between those two numbers.

The tax year itself—2024 versus 2025—matters only because the tax brackets and standard deduction shift slightly each year. But those shifts are usually small. What moves the needle on your refund is your own situation: your income, your deductions, whether you got married, whether you had a child, whether you changed jobs, or whether you changed your W-4 form.

Key Takeaways

  • Your refund size is determined by the difference between what was withheld from your paychecks and what you actually owed in taxes, not by the year itself.
  • If you got a raise, changed jobs, or had a spouse's income added to your household, your withholding may no longer match what you owe, which changes your refund.
  • Claiming a new dependent, buying a home, or starting a side business can shift your refund up or down because they change what you owe.
  • Changing your W-4 form is the most direct way to control your refund size, and you can do it any time during the year.
  • Tax law changes happen most years, but they usually affect only specific groups—check whether any explore to you before assuming your refund will be the same.

Income changes that shift your refund

If your income went up, your refund usually goes down—unless your employer also increased your withholding automatically. Most employers do not. When you get a raise, the same W-4 form stays in place, so the same dollar amount comes out of each paycheck. But you now owe more tax on your higher income. The gap between what was withheld and what you owe grows, and your refund shrinks.

The same thing happens if you changed jobs mid-year. Your new employer starts fresh with your W-4 form, but they may withhold differently than your old employer did, even with the same form. If you worked for two employers in one year, your combined income might push you into a higher tax bracket, which means you owe more than either employer withheld separately.

If your spouse started working, or if you went from married filing jointly to married filing separately, your household income picture changes completely. The withholding that worked for one income no longer works for two. This is one of the most common reasons a refund disappears or becomes a bill.

Life changes that affect what you owe

Having a child, adopting, or becoming a legal guardian changes your refund because you now have a dependent. The child tax credit is worth up to $2,000 per child, depending on your income. That credit reduces what you owe. If the credit is larger than what you owe, the IRS sends you the difference as a refund. If you had no dependent last year and one this year, your refund will likely be larger—unless your income also rose enough to offset it.

Buying a home for the first time means you can deduct mortgage interest and property taxes if you itemize deductions. That lowers your taxable income and what you owe. Selling a home, inheriting money, or receiving a large gift does not directly change your tax bill, but the income from selling an investment property or inherited account does. Getting married, divorced, or widowed changes your filing status, which changes your tax brackets and standard deduction.

Starting a side business or freelance work creates self-employment income that is not subject to withholding. You owe tax on that income, but nothing was taken out of your paychecks for it. Your refund shrinks, or you end up owing money instead.

How W-4 changes control your refund

Your W-4 form tells your employer how much to withhold from each paycheck. If you want a bigger refund, you can claim more allowances or dependents on your W-4, which reduces withholding and leaves more money in your paychecks during the year. If you want a smaller refund or to owe nothing, you can claim fewer allowances, which increases withholding and leaves less in your paychecks.

You can change your W-4 any time during the year. If you realize in March that you are going to owe money, you can submit a new W-4 to your employer when ready, and the new withholding takes effect on the next paycheck. If you realize you are getting too large a refund, you can reduce your withholding the same way. The IRS has a withholding calculator on its website that estimates what you will owe based on your current situation, and it tells you what W-4 entries will get you close to zero refund or bill.

Many people do not change their W-4 even when their situation changes. They keep the same form for years, which is why refunds can swing wildly from one year to the next. The form itself did not change—your life did.

Tax law changes that affect specific groups

Congress changes tax law most years, but the changes usually explore to a narrow group. The child tax credit amount, the standard deduction, and tax brackets all adjust for inflation annually. Those adjustments are small—usually a few dollars or a few percentage points. But they happen every year, so your refund will not be exactly the same as last year even if nothing else changed.

Larger changes happen less often. For example, if you are self-employed, changes to the deduction for business income, or changes to how retirement contributions are taxed, affect what you owe. If you have student loans, changes to the student loan interest deduction affect your refund. If you have rental property, changes to depreciation rules or passive loss limits affect your bill. These changes do not explore to everyone, so check whether any explore to your situation before you assume your refund will follow the same pattern as last year.

The IRS publishes a summary of tax changes each year on its website, organized by topic. If you have income from a specific source—self-employment, rental property, investments, education expenses—search for that topic to see whether the rules changed.

Why comparing year-to-year refunds is not reliable

People often assume that if they got a $3,000 refund last year, they will get roughly the same this year. That assumption fails because it ignores everything that changed. Your income changed. Your family situation changed. Your withholding changed. The tax law changed. Any one of those can swing your refund by hundreds or thousands of dollars.

A better approach is to look at your current situation—your income so far this year, your dependents, your deductions, your W-4 form—and use the IRS withholding calculator to estimate what you will owe or get back. That estimate is based on your actual circumstances, not on last year's number. If the estimate shows you will owe money, you can adjust your W-4 now. If it shows a large refund, you can reduce your withholding to bring that money home during the year instead of waiting for a refund.

Frequently Asked Questions

If I got a big refund last year, will I get one this year?

Not necessarily. A big refund last year means you had too much withheld. If your income, family situation, or W-4 form changed, your withholding may now be closer to what you actually owe, which means a smaller refund. Use the IRS withholding calculator with your current information to estimate this year's refund.

Does getting a raise always mean a smaller refund?

Usually, yes—unless you also adjusted your W-4 to increase withholding. A raise increases what you owe in taxes. If your employer did not automatically increase the amount withheld, the gap between withholding and what you owe grows, and your refund shrinks. You can prevent this by adjusting your W-4 when you get the raise.

Can I control whether I get a refund or owe money?

Yes, through your W-4 form. If you want a refund, claim more allowances to reduce withholding. If you want to owe nothing or break even, use the IRS withholding calculator to find the right W-4 entries. You can change your W-4 any time during the year.

What if I had a major life change mid-year?

Submit a new W-4 to your employer as soon as possible. Life changes like marriage, divorce, a new child, or a spouse starting work all affect what you owe. The sooner you adjust your withholding, the sooner you stop over- or under-withholding for the rest of the year.

How do I know if a tax law change affects me?

The IRS publishes tax changes by topic on its website each year. Search for your income source—self-employment, rental income, education expenses, investments—to see if the rules changed. If you have a straightforward W-2 job with no other income or deductions, most changes will not affect you directly.