Why doesn't my sales tax collected match what I remitted?

Why doesn't my sales tax collected match what I remitted?

Short answer. Because on multiple channels you are not the one remitting all of it. Amazon, Walmart, Etsy and eBay collect and remit marketplace facilitator tax on your behalf, while Shopify collects tax you remit yourself. When both flow into one liability account, the balance grows by the marketplace portion forever and stops representing what you actually owe.

What is the liability account supposed to do?

Sales tax collected is not revenue. It is money you hold briefly on behalf of a state.

The intended cycle has two steps. You collect tax at checkout, which credits a liability. You file and remit, which debits the liability back down. Between filings the balance represents tax collected but not yet paid over.

If you file monthly, the account should approach zero shortly after each filing. If quarterly, it should show roughly a quarter of collections and reset when you remit. A balance that only rises is telling you something is entering that never leaves.

What changed to make this so common?

Marketplace facilitator laws. Every state with a sales tax now requires the marketplace, not the seller, to collect and remit on sales made through that marketplace.

Practically that means an Amazon seller has two completely different tax realities running at once. On Amazon, Amazon collects the tax and Amazon sends it to the state. Your obligation for those sales is already discharged. On your own Shopify store, you collect and you remit.

Both streams pass through your accounting. Only one of them is yours to pay.

This is why the problem barely existed five years ago and is now nearly universal for anyone selling on more than one channel. The accounting setup that was correct in 2018 quietly became wrong.

What does the gap look like?

A CPG brand selling on Shopify and Amazon had $47,300 in the sales tax payable account at year end. The actual amount owed across all filings was $18,900.

The $28,400 difference was marketplace facilitator tax from Amazon sales. Amazon had collected it, Amazon had remitted it to eleven states, and it had also been recorded as a liability on the brand's balance sheet because the settlement entry swept everything into one account.

Nothing was unpaid. No state was owed anything. The balance sheet simply carried a $28,400 liability that did not exist, understating equity by the same amount and giving the founder a nagging sense that he was behind on taxes he had never actually owed.

The reverse version is worse and it happens too. If marketplace tax is booked into revenue rather than a liability, revenue is overstated by the tax amount and the error compounds every settlement.

What else drives a mismatch besides marketplaces?

Five things, in rough order of how often they matter.

Returns and refunds. Refunding a sale refunds the tax with it. If the refund reverses revenue but not the tax liability, the balance drifts upward by the tax on every return. On a business with a 20 percent return rate, that adds up quickly.

Discounts applied after tax calculation. The taxable base is the discounted price. A platform configured to calculate tax before applying a discount collects slightly too much, and the difference accumulates invisibly across thousands of orders.

Rounding. Tax is calculated per line, remitted on a total. Fractions of a cent across tens of thousands of transactions produce a small persistent difference. This one is normal and does not need fixing, but you should be able to recognize it so it is not mistaken for something else. If the residual after every other explanation is under a few dollars a month, it is rounding.

Collecting where you do not file. A platform configured to collect in states where you have no registration means you are holding tax with nowhere to send it. This is a genuine exposure, not just a reconciliation issue, because collected tax that is never remitted belongs to the state regardless of whether you registered.

Shipping treated inconsistently. Some states tax shipping, some do not, and platform defaults do not always match the actual rule. Both directions cause a mismatch, and the one where you undercollected is the expensive one.

How do you find out where the gap is?

Work in this order. Each step removes a category, so the residual gets smaller and more diagnosable.

Split the liability by channel first. This single change explains most of the gap in most businesses. Create separate accounts, for example Sales Tax Payable for tax you remit and Marketplace Facilitator Tax for tax the marketplace handles. The second should net to zero within each settlement.

Pull the tax collected report from each platform for a full quarter. Shopify and Amazon both produce these. Compare the total to what hit each liability account. Differences at this stage are mapping problems inside the integration.

Compare collected to filed, state by state. Take one quarter, one state, and tie the platform report to the return you filed. Doing this for your largest state usually reveals whichever systematic issue is present, and the same issue is normally running everywhere else.

Check the state list. Compare where you are registered against where each platform is collecting. Any state where you collect and do not file needs attention now rather than later.

Whatever is left after those four is usually rounding, and usually immaterial.

How should this be set up so it stays clean?

Separate accounts by channel. Not classes or tags. Separate liability accounts, because the two streams have different lifecycles and mixing them is the original error.

Marketplace tax should net to zero inside each settlement entry. Amazon collects it and remits it, so it should enter and leave your books in the same journal entry. If it is accumulating, the entry is incomplete.

Reconcile monthly as a named close step. Compare each liability account to the platform report before calling the month closed. Two minutes when it is healthy, and it prevents a year-end surprise like the $28,400 above.

Keep a registration matrix. A simple table of states, registration status, filing frequency, and which channels collect there. Nexus changes as sales grow and as inventory moves between warehouses, so this needs a review each year rather than being set once.

What about nexus, since inventory moves?

Worth separating from the bookkeeping, because it is the part with real exposure attached.

Amazon handling marketplace tax does not eliminate your own obligations in states where you have nexus from other activity. Inventory stored in an FBA warehouse creates physical presence in most states that assert it. Direct sales into a state can create economic nexus once thresholds are crossed, commonly $100,000 in sales or 200 transactions, though both the numbers and the rules vary and several states have changed them.

So a seller can owe registration and filing in a state where Amazon already remits all the Amazon tax, because the Shopify sales into that state are theirs to handle.

That is a question worth answering deliberately with someone who does this work, rather than assuming the marketplace covered it. The accounting cleanup above will not tell you where you have nexus. It will only tell you where you are collecting, which is a different question and sometimes the first clue that the two do not match.

What does the correcting entry actually look like?

Once you know how much of the balance is marketplace tax, the cleanup itself is straightforward. It is the diagnosis that takes the time, not the entry.

Using the example above, $28,400 of the $47,300 balance was Amazon tax already collected and remitted by Amazon. That amount was never an obligation, so it has to come off the liability. Where the other side goes depends on how it got there.

If it was booked as a liability against revenue, meaning revenue was reduced when the tax was recorded, the correction debits Sales Tax Payable $28,400 and credits Sales. Revenue was understated by that amount and this restores it.

If it was booked as a liability against a settlement clearing account, the correction debits Sales Tax Payable and credits the clearing account, which should then resolve as part of normal settlement reconciliation.

If it originated in prior years and those returns are filed, the adjustment belongs in retained earnings rather than the current year's income statement, and it is a conversation with whoever prepares the return before it gets posted. Moving $28,400 into current year revenue when it was earned across three prior years creates a different misstatement in place of the old one.

Document the calculation before posting. A single journal entry moving $28,400 with no supporting detail is exactly the kind of thing that gets questioned in diligence, and reconstructing the reasoning a year later is far harder than writing it down now. Attach the settlement summary showing the marketplace portion by period, and note which states were involved.

Why does this sit unnoticed for so long?

Because a growing liability looks like caution rather than error.

Nobody investigates an account that suggests they owe more than expected. It reads as conservative. The instinct is that a large tax payable balance means you are covered, and the number gets left alone precisely because it feels safe.

It also never breaks anything visible. The bank reconciles. Revenue reports look right. Filings get made on numbers pulled from the platform rather than from the accounting system, so the two never have to agree.

The gap surfaces at year end, during a financing conversation, or when a buyer asks why the tax liability is three times the quarterly filing. By then it has been accumulating for years, and unwinding it means reconstructing which portion was marketplace tax across every settlement in the period.

Twenty minutes a month prevents the entire thing. Almost nobody spends it, because nothing is visibly wrong until suddenly it matters a great deal.

Common questions

Do I still need to file in a state where Amazon remits everything? Sometimes yes. If you have nexus there and sell through any other channel into that state, those sales are yours. Registration status and channel mix determine it, not the marketplace.

Should marketplace facilitator tax appear in my revenue? No. It is neither revenue nor expense. It passes through and nets to zero in the settlement entry.

Why does my Shopify tax report not match my filing? Usually returns, post-tax discounts, or shipping taxability. Compare one state for one quarter and the pattern becomes obvious.

Is a small persistent difference a problem? A few dollars a month is rounding across per-line calculations and is normal. Anything larger has a cause worth finding.

What if I have been collecting in a state where I never registered? Address it promptly. Collected tax belongs to the state whether or not you registered, and most states offer voluntary disclosure programs that limit look-back and penalties for sellers who come forward first.

Does tax automation software fix this? It fixes calculation and filing. It does not fix a chart of accounts that puts two different tax streams in one bucket, which is where this specific problem lives.

How far back should I clean up? Far enough to know the true liability today, so usually the current year plus enough of the prior year to establish the pattern. Correcting the opening balance matters more than restating every month along the way.

Who should own this reconciliation? Whoever closes the month, as a named step with the platform reports attached. It fails when it belongs to the person who files the returns, because they work from platform data and never compare it back to the accounting system, which is precisely where the gap hides.

What if I sell internationally? VAT and GST work differently and need their own liability accounts, never the domestic sales tax account. Marketplaces often handle collection abroad as well, which creates the same pass-through pattern in a second currency.

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FynScale is a boutique AI consulting firm for accounting and finance. AI speed. Human judgment.