5 Payroll Mistakes That Trigger IRS Penalties
Common missteps in deposit timing, worker classification, and quarterly filings — and how to avoid them.
Published July 2026 · General information, not personalized tax advice — see note below.
1. Depositing payroll taxes late
Withheld income tax, Social Security, and Medicare aren't yours to hold onto — the IRS expects them deposited on a schedule based on your total payroll tax liability, which can be monthly or semi-weekly depending on your business's size. Missing a deposit deadline, even by a day, can trigger a penalty that scales with how late the deposit is. This is one of the most common — and most avoidable — payroll mistakes, especially for businesses that process payroll themselves without a fixed deposit calendar.
2. Misclassifying employees as independent contractors
Paying someone as a 1099 contractor when the IRS would consider them a W-2 employee (based on how much control you exercise over their work, schedule, and tools) doesn't just create a payroll problem later — it can mean back taxes, penalties, and interest once discovered, sometimes going back multiple years. If you're unsure how a worker should be classified, it's worth a real review rather than a guess.
3. Getting withholding calculations wrong
Federal and Maryland withholding both depend on the employee's filing status, allowances or dependents claimed, and current-year tax tables. Using outdated tables, or not updating an employee's withholding after they submit a new W-4, leads to under- or over-withholding that surfaces at tax time — for them, and sometimes as a compliance issue for you.
4. Missing quarterly payroll tax filings
Beyond depositing the tax itself, employers generally need to file a quarterly federal payroll tax return (Form 941) reporting wages paid and taxes withheld, plus corresponding Maryland filings. A missed or late filing can draw its own penalty separate from any deposit issue — even if the tax itself was paid on time.
5. Poor payroll recordkeeping
If the IRS or Maryland Comptroller ever questions a filing, your records — pay stubs, timesheets, W-4s, deposit confirmations — are what resolve it quickly instead of turning into a drawn-out back-and-forth. Sloppy or missing records don't cause a penalty by themselves, but they make every other mistake on this list much harder and more expensive to fix.
The pattern behind all five
Many payroll penalties trace back to the same root cause: payroll being run without a fixed schedule, checklist, or second set of eyes. None of these mistakes require complex tax knowledge to avoid — they require consistency, which is exactly what outsourcing payroll processing is meant to solve.
A note on this article: this is general information for Maryland small businesses, not tax, legal, or accounting advice for your specific situation. Worker classification rules and payroll tax deposit/filing requirements are set by the IRS and the State of Maryland and can change — always confirm current requirements at IRS.gov or marylandtaxes.gov, or talk with our team about your situation before acting on it.