Prior Year Unfiled Returns

Sam sat down and put a manila folder on the desk.

Inside were W-2s and 1099s from three different years. He pushed the folder across the table without making eye contact.

“I haven’t filed in a while,” he said.

“How long is a while?”

“Three years. Maybe four. I’m not sure about the fourth.”

The preparer picked up the folder. Tax years 2021, 2022, 2023. She checked the documents. W-2s from his old employer, some 1099s from when he did contract work.

“Okay,” she said. “This is fixable. It’s going to take some work, but there’s a clear path forward. Let me ask you a few questions and we’ll figure out where to start.”

Sam exhaled like he’d been holding his breath for months. Because he had.

Prior year unfiled returns are more common than most people realize. Life happens. People fall behind. The longer they wait, the more intimidating it feels, and the more it compounds. Your job as a preparer is not to judge — it’s to be the calm, organized professional who helps them get back on track.

Understanding why clients don’t file helps you have the right conversation when they finally come in. It’s almost never deliberate defiance. The most common reasons:

They thought they didn’t need to. Their income dropped. They moved. Someone told them they didn’t make enough. Life got complicated.

They owed money and were afraid. This is the most common reason. They knew they owed from a prior year, couldn’t pay, and instead of working something out, they just stopped filing. Every year felt harder to start again.

Life got in the way. Divorce, illness, job loss, a death in the family. Sometimes the practical stuff falls through the cracks for a year or two before anyone notices.

They were scared of what they’d find. Self-employed people especially — they know they didn’t make quarterly payments. They’re afraid to find out exactly how much they owe. Avoidance feels easier than knowledge, until it doesn’t.

When someone stops filing, the IRS doesn’t forget about them. The IRS receives copies of W-2s and 1099s from employers and financial institutions. They know income was earned. Eventually, one of two things happens:

The IRS files a Substitute for Return (SFR). If someone doesn’t file, the IRS can prepare a return on their behalf using the information they already have. This sounds helpful. It isn’t. The SFR uses the least favorable filing status (Single), claims no deductions beyond the standard deduction, and claims no credits. It calculates the maximum possible tax. The IRS then sends a notice saying: this is what you owe.

Penalties and interest compound. Failure-to-file penalty: 5% per month up to 25%. Failure-to-pay penalty: 0.5% per month from April 15. Interest on unpaid balances. Each year this compounds. A $3,000 original tax bill from 2021 can become a $5,000+ problem by 2025 without the taxpayer doing anything.

Step 1: Figure out which years need to be filed. The IRS generally focuses on the most recent six years for compliance purposes. But if the client owes money, older returns may still matter. Start by gathering documents for all unfiled years.

Step 2: Gather the income documents. W-2s and 1099s from prior years can be requested directly from the IRS using Form 4506-T or through the IRS online transcript tool. Many clients don’t have their old documents — this is how you get them.

Step 3: Prepare and file the returns in order. Oldest first. Each year’s return uses the tax law, rates, and thresholds from that specific year — not current year numbers. Your software should have prior year modules. If not, the IRS website has historical forms.

Step 4: Calculate the total liability. After all returns are filed, you’ll know the actual tax, penalties, and interest across all years. The IRS will assess this and send a formal notice.

Step 5: Set up a payment plan if needed. If the client can’t pay in full, the IRS Installment Agreement program allows monthly payments. For amounts under $50,000 combined, the approval process is largely automatic. For larger amounts, more documentation is required.

The three-year refund statute is one of the most important things to communicate to a client with unfiled prior years. For each year, the window to claim a refund closes three years after the original due date.

A 2021 return (original due date April 18, 2022) has a refund window that closes April 18, 2025. If Sam had a refund coming in 2021 and he walks in after that date — the refund is gone. Forever. Even though the IRS will still require him to file and may still have a balance due for other years.

This is why you never wait when a client mentions unfiled prior years. Pull out the calendar. Figure out which years are approaching their refund window. File those first.