You got a letter from a state. Maybe it says you have an unpaid balance. Maybe it says you never filed at all. Either way, your first question is probably the same one we hear from sellers every week:
Am I screwed?
The short answer: probably not. But what you do (and what you avoid doing) in the days after receiving a past due sales tax notice matters more than most sellers realize.
There is a number that has been quietly growing inside your business, and this letter just made it visible. The good news is that most of the damage is still fixable. Some of it is even negotiable. But your options narrow fast the longer you wait, and they narrow even faster if you respond wrong.
Here is everything you need to know.
In this post:
- What a past due sales tax notice usually means
- What to do in the first hour after getting a notice
- What NOT to do when you receive a past due notice
- What is the difference between non-filing and filing late?
- Can penalties on a past due sales tax notice be waived?
- When does your control over this situation change?
- When should you get professional help with a sales tax notice?
- What does getting compliant actually look like?
Key Takeaways
- A past due sales tax notice usually means one of two things: a missing return or an unpaid balance. They are handled differently, and knowing which one you have shapes everything that follows.
- Do not ignore the notice and do not guess your way through a response. Both make the situation worse.
- Penalties can often be eliminated through a Voluntary Disclosure Agreement (VDA) if you act before the state escalates. Interest cannot be waived — it compounds from day one.
- Non-filing and late filing are not the same thing. States treat them differently, and the consequences reflect that.
- Once a state contacts you, you are on their timeline. Getting ahead of this — before more letters arrive — gives you far more options.
What Does a Past Due Sales Tax Notice Actually Mean?
Not all sales tax notices mean the same thing, and the type of notice you received determines what needs to happen next.
Most past due notices fall into one of two categories:
You have a missing return.
The state has a record that you registered (or that you should have registered) but one or more returns never came in. This is a non-filing situation. The state does not yet know what you owe. They just know you have not filed. This type of notice is about compliance: they want the return, not just the money.
You have an unpaid balance.
The state received a return but no payment, or their records show a balance that was never settled. This is more straightforward to resolve but can carry interest and penalties that have been accruing since the original due date.
In some cases, the notice covers both: a period with unfiled returns and a balance from a period where you did file. Reading the notice carefully to understand which situation applies to you is the first thing that matters.
The bottom line: A past due sales tax notice is the state telling you they have noticed a gap. It is not necessarily a full audit or a final demand, but it is a signal that the clock has started.
For more on types of notices and questionnaires states are sending about sales tax, read What Sales Tax Pre-Audit Questionnaires Mean for Your Ecommerce Business [+ How to Respond].
What to Do in the First Hour After Getting a Sales Tax Notice
The first hour is not the time to call the state. It is the time to get oriented.
Do this first:
- Read the notice completely. Identify the state, the tax period in question, the type of issue (missing return or unpaid balance), any response deadline, and any reference or case number.
- Pull your sales records for that state and period. Do not wait on this. You need to know what you actually collected, when your nexus started, and whether you were registered at the time.
- Note the response deadline. States typically give 30 to 60 days. Missing that window can escalate the situation significantly.
- Do not assume the amount on the notice is correct. States often estimate based on incomplete data. The actual amount you owe may be higher or lower.
Getting clear on exactly what you are dealing with before you respond, or before you call anyone, is the single most useful thing you can do first.
The bottom line: Read it carefully, gather your data, note the deadline. Do not react before you understand what you are responding to.
What NOT to Do When You Receive a Past Due Sales Tax Notice
This is where a lot of sellers make things worse without realizing it.
Do not do this:
- Do not ignore it. A past due notice that goes unanswered often escalates to a lien, a levy, or an enforced audit. States have more tools than most sellers expect, and silence is interpreted as avoidance.
- Do not guess on your response. If you are unsure what period is at issue, what you collected, or what nexus rules applied to your business at the time, sending a response with incorrect numbers can create a new problem on top of the original one.
- Do not just pay the number on the notice without verifying it. The state’s estimate may be based on third-party data that overstates what you owe. You may be paying more than necessary.
- Do not assume this state is the only one watching . States share data and cross-reference marketplace activity. A notice from one state is sometimes a signal that others are not far behind.
- Do not call the state without knowing what you are going to say. Once you open a dialogue, whatever you say on that call can shape the direction of the inquiry. Know your facts before you engage.
The bottom line: Ignoring the notice and guessing your way through a response are the two moves most likely to make this harder to resolve. Neither buys you time — they just create more exposure.
What Is the Difference Between Non-Filing and Filing a Late Sales Tax Return?
This is one of the most important distinctions sellers do not know, and it directly affects how a past due notice is handled.
If you filed late:
States see it as an administrative delay. You owe penalties and interest, but the situation is contained. They look back to when you registered. The conversation is about catching up, not investigating.
If you never filed at all:
States interpret that differently. They want to understand the full scope of what happened. That can mean looking back further → more years, more liability, more to sort through. The inquiry is broader by default.
Late filing says: I knew, but I was delayed. Non-filing says: I either did not know, or I chose not to. The state responds differently to each, and that difference shows up in how far back they look and what they ask for.
The bottom line: Filing late and never filing are not the same thing. One is a delay. The other opens the door to a much bigger conversation with the state. If you are behind, filing something is always better than filing nothing.
Can Penalties on a Past Due Sales Tax Notice Be Waived?
When you are behind on sales tax, you face two types of costs. Most sellers do not know that only one of them is negotiable.
Penalties can often be waived.
Penalty rates vary by state, and can be as high as 50%. But if you come forward before a state escalates, through a program called a Voluntary Disclosure Agreement, or VDA, most states will waive those penalties entirely. Under a VDA, that number could be zero.
Once you have received a notice and the state has opened a case, your ability to use a VDA in that state is typically gone. But if you have exposure in other states that have not yet contacted you, VDAs are still on the table there.
Interest cannot be waived.
Interest compounds from the day the tax was due. Most states charge between 6% and 12% annually. There is no negotiating it away. You owe it from day one, no exceptions.
The bottom line: Every month of delay locks in more interest you will never recover. The penalties are a different story, but only if you act before the state comes to you. For the state that already sent the notice, focus on accuracy and response. For every other state you have exposure in, this is the moment to get ahead of it.
For more on how VDAs work, read A Guide to Voluntary Disclosure Agreements (VDAs) for Ecommerce Businesses.
When Does Your Control Over a Sales Tax Situation Change?
There is a point where the dynamic shifts. Most sellers do not realize it until they are already past it.
Before a state contacts you:
- You assess your own exposure.
- You choose which states to address first.
- You can file VDAs where they make sense.
- You set your own timeline.
After a state contacts you:
- You are working on their timeline.
- You are answering their questions.
- You are providing what they request.
You still have options after receiving a letter. You can provide documentation, negotiate payment plans, and work through it. But you are responding to their process, not running your own.
Think of it like this: it is the difference between scheduling a checkup because you want to stay healthy versus responding to symptoms that showed up unexpectedly. Same underlying situation. Very different level of control.
The sellers who end up in the best position are almost always the ones who got clarity on their exposure first BEFORE the letters started arriving. If you are reading this because you just got a notice, the question is not just how to handle this state. It is whether other states are close behind.
The bottom line: Early action costs less and gives you more choices. Later action still works. You just have fewer options and less say in how it unfolds.
When Should You Get Professional Help With a Sales Tax Notice?
Not every sales tax notice requires outside help. But some situations clearly do, and waiting to bring someone in when you need them is one of the more costly mistakes sellers make.
You should get professional help if:
- The notice involves multiple periods or multiple years of unfiled returns.
- The amount the state claims you owe does not match your own records.
- You have nexus in other states and have not filed there either.
- The notice references an audit or a formal examination.
- You are unsure what nexus you had in the state and when it started.
- The response deadline is within the next two weeks.
A sales tax professional can verify whether the state’s numbers are accurate, identify whether a VDA is still available in other states, handle communication with the state on your behalf, and build a plan that covers the full scope of your exposure, not just the state that wrote first.
The cost of getting help early is almost always lower than the cost of responding incorrectly and dealing with what comes next.
The bottom line: If the situation involves more than a single period with a straightforward balance, get professional guidance before you respond. The response you send shapes everything that follows.
For more on what a sales tax audit looks like and what triggers one, read Sales Tax Audits Guide: What’s Triggering Them and What Sellers Need to Know.
What Does Getting Compliant After a Sales Tax Notice Actually Look Like?
Here is what we see when sellers decide to stop deferring and start fixing.
They come to us knowing they have exposure but unsure how much or where. We walk through their situation together. We identify which states they have nexus in, calculate realistic numbers, and map out a clear plan.
And then something shifts. The fear of the unknown becomes a plan for something known.
They learn which states need VDAs, which need simple registration, what the timeline looks like, and what the real cost is. Within 90 to 120 days, most sellers are fully compliant — collecting tax correctly, filing regularly, with payment plans in place for any back taxes owed.
The constant low-level stress of “I should deal with this” gets replaced with “It is handled.”
The bottom line: Getting compliant is not as painful as most sellers expect. The hardest part is getting a clear picture of where you actually stand. Once you have that, a plan comes together fast.
Got a Past Due Sales Tax Notice? Find Out Exactly Where You Stand.
If you received a notice, the right next step is not to panic. It is to get clarity on your full exposure before you respond.
Start with our free Sales Tax Risk Assessment. Answer 18 quick questions and walk away with your risk level and a prioritized action plan in about five minutes.
Start your free assessment →If you already know you have exposure across multiple states and you are ready to get it handled, our sales tax team works with seven and eight-figure ecommerce sellers every day. We can verify the state’s numbers, identify VDA candidates, handle communication on your behalf, and build a plan that protects your cash flow.
The notice you received is a signal. What you do next determines how this ends.
