With Tax Day arriving this week on April 15, millions of filers are rushing to submit their returns—a period that tax experts say often increases the chances of simple but costly mistakes. Even minor errors, such as incorrect personal details or overlooked income, can delay refunds, trigger IRS notices, or lead to penalties that take time and money to fix. The good news, according to tax professionals, is that most of these issues are entirely avoidable with extra attention and preparation.

Here are the five most common filing mistakes to watch out for, according to tax experts and the IRS:

What the Right Is Saying

Conservative tax policy experts are emphasizing personal responsibility and accurate filing to avoid penalties. Mike Faulkender, co-chair of American Prosperity at the America First Policy Institute and a former Treasury official and IRS commissioner, stressed that taxpayers need to pay by the deadline even if they request an extension. 'Remember that even if you claim an extension, the money is owed on April 15,' Faulkender said. 'You have to actually send in a check or have the payment deducted from your account by the filing deadline.'

Conservatives also emphasize the importance of verifying income before filing. Faulkender noted that taxpayers can create an account on IRS.gov to see what has been filed under their tax ID number. 'If you're missing one, or you misplaced it, rather than requesting it again, you can actually go and see what was filed under your taxpayer identification number,' he said. This aligns with conservative principles of self-reliance and careful financial management.

What the Left Is Saying

Progressive tax advocates and consumer protection groups are emphasizing the importance of ensuring taxpayers claim every credit and deduction they deserve. Bill Sweeney, senior vice president of government affairs at AARP, urged filers not to rely on last year's return as a blueprint because of recent changes to the tax code from the One Big Beautiful Bill Act. 'This would be a good year, given that there are these changes to the tax code, to make sure not to assume that what you did last year will convey over to this year,' Sweeney said. 'Really take a fresh look at your tax situation and see if there's money that you're leaving on the table.'

Consumer advocates note that lower-income taxpayers and seniors are particularly vulnerable to missing deductions, as the tax code remains complex despite legislative changes. Progressive groups have long advocated for simpler filing processes and greater outreach to ensure vulnerable populations don't miss out on benefits like the Earned Income Tax Credit.

What the Numbers Show

According to IRS data, filing status errors are among the most common triggers for audit reviews. The head of household designation, which comes with a larger standard deduction and more favorable tax brackets, has strict requirements tied to paying more than half the cost of keeping up a home and having a qualifying dependent. Taxpayers who incorrectly claim head of household status may have to pay back tax benefits later, plus penalties and interest.

The IRS processes more than 150 million individual tax returns annually. Errors in bank account information for direct deposit or direct debit can lead to rejected payments, resulting in penalties and interest that accrue on top of any tax bill owed. Tax experts estimate that millions of returns require correction each year due to simple data entry errors.

The Bottom Line

With the April 15 deadline approaching, taxpayers should take time to verify their filing status, ensure all income documents have been received, and double-check banking information before submitting their returns. Experts recommend using the IRS online filing-status tool and creating an account on IRS.gov to verify reported income. Those who cannot pay in full should pay what they can to limit penalties and interest. For anyone uncertain about their situation, the IRS offers resources and many tax software programs include guided questions to help filers choose the correct category. The key message from tax professionals on all sides: a little extra attention now can prevent costly problems later.