What the Platform Collects, and What’s Still Yours

When economic nexus arrived, states faced an enforcement problem: chasing thousands of small sellers individually was impractical. So they pushed the obligation up the chain to the platforms.

Under marketplace facilitator rules, a qualifying platform collects and remits sales tax on transactions made through it. For sellers who operate only on one big marketplace, that removed most of the burden overnight.

For everyone else, it created a split that the books have to reflect.

The split

If you sell through more than one route — and most sellers eventually do — your sales fall into two buckets:

Facilitated sales. Through a qualifying marketplace. The platform collects the tax and remits it under its own registration. That tax was never yours; it should not appear in your revenue or your liability accounts.

Direct sales. Your own website, wholesale orders, phone orders, trade shows, anything not through a facilitator. Here you are the seller of record. If you have nexus in the buyer's state, collecting and remitting is your obligation.

The same product, sold on the same day, at the same price, can carry completely different tax handling depending on which channel it went through.

Where it goes wrong

Assuming the platform covers everything. The most common and most expensive error. A seller does 85% of volume through a marketplace, sees tax handled there, and concludes sales tax is taken care of. The 15% through their own site is unregistered, uncollected, and accruing.

Booking facilitated tax as revenue. If your import records the gross including tax the platform collected, revenue is overstated and there is a phantom liability that never clears.

Not knowing whether facilitated sales count toward your threshold. States differ. Some include marketplace sales when measuring whether you have crossed; others exclude them. In an including state, a seller doing $90,000 direct and $60,000 marketplace may have crossed a $100,000 threshold on their direct sales obligation, which is a genuinely counterintuitive result.

Registration does not always go away

Even where a platform handles everything, some states still expect a registered seller to file — sometimes a zero return, sometimes a return reporting facilitated sales as exempt.

Stopping filing because the tax is handled elsewhere can produce delinquency notices for a business that owes nothing. Whether you can deregister, or must keep filing, is state-specific and worth confirming rather than assuming.

What the books need to do

One thing, done consistently: keep the two channels separable.

Facilitated sales recorded with the tax excluded, tagged to the channel. Direct sales recorded with tax as a liability, by state. Then at filing time you can produce a return covering exactly the sales that are your responsibility, and it will tie.

Books that record a single blended revenue figure cannot do that. The reconstruction is possible but tedious, and it has to be redone every filing period rather than once.

We handle the channel separation under e-commerce bookkeeping and the filing side under sales tax filing support. The state directory carries the current threshold and administering agency for each state.

Whether a specific platform qualifies as a facilitator in a specific state, and whether you can deregister, are determinations worth taking to your CPA or a state tax professional. We make sure the numbers underneath are right.