US sales-tax monitoring for online sellers

Know where you owe sales tax, before the state does.

Every state has an economic-nexus threshold. Cross one without registering and the back taxes, penalties, and interest are yours. NexusRadar watches all of them — for one flat price, with no per-filing fees, ever.

Built for Shopify, Amazon, and Stripe sellers under $1M in revenue — the ones enterprise tools overcharge and over-complicate.

01

Where have you triggered nexus?

Enter your annual sales and order count per state. We check each against that state's current economic-nexus threshold and tell you exactly where you need to register and start collecting. Nothing leaves your browser.

Your sales by state — add the states you ship to
Paste sales by state (CSV)
No states yet. Add the states you sell into, or load the common high-volume ones to start.
0
states where you've triggered nexus — register & collect now
0
approaching a threshold — watch these closely
0
monitoring — well under the line
02

What rate do I collect?

A quick average combined rate (state + typical local) for any state, for collection planning.

03

One flat price. No filing tax on top.

Incumbents advertise a low base price, then bill per filing, per state, and per registration. For a seller in five states filing monthly, that quietly becomes hundreds a month. We don't do that.

Flat, all-in
$29/mo
  • Every US state monitored
  • Unlimited transactions
  • Threshold + approaching alerts by email
  • Current collection rates
  • No per-filing fees
  • No per-state charges
  • No annual contract
Start with the free check
All-in annual cost — a seller under $1M, 5 states, filing monthly
ProviderModelEst. all-in / yr

Figures are representative published-pricing estimates for the stated profile (subscription + per-filing + registration where applicable); actual quotes vary. Sourced in the opportunity brief. NexusRadar does not file returns — see “What it does” below.

04

What it does — and what it deliberately doesn't

The expensive, error-prone part of sales tax is knowing where you owe and what to collect. That's what we do. Filing itself is cheap and we hand it to you or your accountant clean — which is why we can stay flat.

NexusRadar does

  • Track economic nexus in all 46 taxing jurisdictions
  • Alert you before and when you cross a threshold
  • Tell you which states to register in, and when
  • Give you the rate to collect per state
  • Produce a monthly per-state collected-tax summary to file from

NexusRadar doesn't

  • File returns for you (that's where per-filing fees come from)
  • Register you with states (we show you the link + what you need)
  • Give tax or legal advice
  • Lock you into a contract
  • Charge more as you grow into more states
05

Questions sellers actually ask

What is economic nexus?

Since the 2018 South Dakota v. Wayfair Supreme Court decision, a state can require you to collect its sales tax once your sales into that state cross a threshold — typically $100,000 in sales, or a set number of transactions — even if you have no physical presence there. Cross it unknowingly and you're liable for the tax you should have collected, plus penalties and interest.

Why does this cost hundreds a month elsewhere?

Because most tools bundle filing and charge for it — per return, per state, per registration. If you sell into five states and file monthly, that's sixty filings a year on top of the base subscription. NexusRadar separates the two: we monitor and calculate for a flat fee, and leave the (cheap, occasional) filing to you or your bookkeeper.

Do you file my returns?

No — on purpose. Filing is where the runaway fees live. We give you a clean per-state summary of what you collected so filing takes minutes, either yourself through the state portal or by handing it to your accountant.

Is my sales data safe?

The nexus checker on this page runs entirely in your browser — nothing is sent anywhere. The paid product connects to your Shopify/Amazon/Stripe sales read-only to keep the numbers current.

Is this tax advice?

No. NexusRadar is informational software to help you monitor thresholds and plan collection. For advice specific to your situation, talk to a licensed tax professional.