NOTICENINJA – the inbound side of tax compliance
1stopVAT gets you registered and filed in every jurisdiction where you sell. NOTICENINJA handles what comes back.

NATURE OF THE PARTNERSHIP
About 1stopVAT & NOTICENINJA
Once a business is registered in multiple states and countries, the notices start arriving: assessments, penalty letters, information requests, refund confirmations, address verifications. They come by mail, email, and portal, in different languages and formats, each with its own response window. Most companies track them in a spreadsheet, a shared inbox, or someone’s memory – that’s where penalties, interest, and lost refunds come from.
What we cover:
- 1stopVAT: End-to-end VAT management – from registration and filing to strategic consulting – across 100+ jurisdictions worldwide.
- NOTICENINJA: A purpose-built platform for tax notice management. Kata™, our AI ingestion engine, reads every notice on arrival, extracts the jurisdiction, tax type, notice type, amount, and due date, and routes it into a workflow with the deadline already on the clock.
MUTUAL BENEFITS
How collaborative support works

Get registered, stay on top of what comes back
1stopVAT ensures you’re registered and filing correctly in every market. NOTICENINJA makes sure nothing that arrives afterward – a penalty letter, an assessment, a refund notice – slips through the cracks.

One system, full audit trail
Notices route to the right person on your team or your 1stopVAT advisor, with escalation rules so nothing stalls. Every action is logged, giving you reporting you can hand to leadership, auditors, or an acquirer.

Recover money that’s already yours
Penalty abatement and refund tracking mean overpayments and unclaimed refunds don’t just sit in state accounts. Proven at scale: 9M+ notices processed, 500K+ businesses, 170+ countries, 95 languages translated.
Together, 1stopVAT and NOTICENINJA cover both directions of tax compliance – outbound registration and filing, and inbound notice management – so nothing falls through the gap between the two.
Check our blog post
US Sales Tax Notice Management for Multi-State Businesses
A guest article from NOTICENINJA on why notice management is a distinct operational challenge once you’re registered in multiple states, and what a functioning notice-handling process requires.


Join us and make your business life easier!
There is no time to wait – take action today!