A backfiled return, or "backfiling," is a sales tax return for a past period where no return was ever filed. It's different from an amendment, which corrects a return that was already filed. This article covers when you'll need one, what it costs, how long it takes, and what we need from you.
When you'll need a backfiling
The most common reason: you crossed nexus in a state before you registered there.
When you register, choosing "First month of exposure" registers you back to the month you crossed nexus and creates the backfilings needed to bring your account current. You can also need backfilings if you're already registered somewhere and have past-due returns — for example, a prior provider missed filings.
Cost and timeline
Our standard fee is $150 per backfiled return. This covers our work to prepare and file the return; any tax due, penalties, or interest owed to the state are separate.
Plan on 30 to 60 days once your registration or transfer is complete and we have access to your state portal—backfilings can’t start before that.
🟡 Let us know up front if you have significant past-due tax obligations or think you may need backfilings. Once a state sets the date you became responsible for collecting and filing tax, it’s generally difficult to change unless you meet very specific criteria.
Letting us know early helps our team make sure we have the right account access from the start, review your history with you, and walk through what’s needed so you know what to expect.
🔴 Another thing to keep in mind: Most states charge penalties and interest on past-due returns. Alabama is a partial exception to the timeline above because these charges can add up quickly. For Alabama backfilings, our team will need your sign-off before we submit the return, even once your registration or transfer is complete.
What you owe and what we need from you
If you didn’t collect tax during those past periods, you’re responsible for paying the uncollected tax—we can’t go back and collect it from past customers. States may also assess penalties and interest, which remain your responsibility because those periods predate your relationship with our team.
🔵 In some cases, you may be eligible for a penalty waiver. Reach out to your team for guidance on whether you qualify and how to submit a waiver request to the jurisdiction. While we don’t submit penalty waiver requests on your behalf, we can help point you in the right direction.
Be sure to have your historical sales data for the applicable period(s) and copies of any state notices ready before reaching out so our team has what we need to get started.
If your records are incomplete
If your records for a backfiled period are incomplete, tell us as soon as you know. We'll calculate the return off whatever data is available rather than waiting, but a number built from partial data can be wrong—including showing less tax than you actually owe. Once complete data comes in, we'll reprocess that period and flag it for recalculation.
💬 Questions? Reach out to our team anytime via the messaging widget in your Numeral dashboard.