Now piloting with US CPA firms

Purpose-built AI for compliance, advisory and audit.

Onsen handles the high-leverage workflows partners can't delegate — research, document analysis, engagement prep, and review — with a defensible decision record on every action.

Free 30-day pilot · No credit card · QuickBooks Online required

Built for QuickBooks Online · SOC 2 Type II in progress · US-based team A vertical AI platform for accounting — not a general chatbot.

Four agents. One job: get your firm out of the weeds.

Each Onsen agent handles one well-scoped piece of repeating work. They run on a schedule, hand off to each other, and put humans in the loop only where it matters.

Transaction Categorizer

Reads your QuickBooks transactions, proposes a categorization with reasoning, and queues the edge cases for human review. No more end-of-month batching.

Document Collector

Chases clients for the missing 1099, the bank statement, the receipt — over email — and stops chasing the moment it lands.

Deadline Monitor

Knows the federal and state calendar. Tells you who is at risk this week, not the week after the deadline passed.

Month-End Close

Runs the recurring checklist — reconciliations, accruals, review prep — and hands you a close package, not a to-do list.

How it works

No new portal for your clients. No rip-and-replace of your stack. Onsen plugs into the systems you already use.

  1. 01

    Connect QuickBooks + Gmail

    Read-only OAuth. Five minutes. No new logins for your clients.

  2. 02

    Pick your workflows

    Turn on the agents you want. Each one runs in the background and reports in.

  3. 03

    Review and approve

    Every action shows up in a queue with the reasoning. You approve, edit, or override.

  4. 04

    Audit-ready by default

    Every decision is logged with sources, timestamps, and operator. Workpapers for the AI.

Workpapers for the AI.

Every action an Onsen agent takes is recorded as a Decision Record — the source it read, the reasoning it followed, the human who approved it. If your partner asks "why did the AI do that?", you have a defensible answer in two clicks.

  • Full chain of custody on every transaction touched
  • Human-in-the-loop approval for anything above your threshold
  • Exportable audit log — CSV, PDF, or read-only portal
  • Read-only QuickBooks scopes by default; writes require explicit opt-in
# decision_record · TR-48391
agent: transaction_categorizer
client: Acme Holdings LLC
txn: AMEX · $4,128 · 2026-06-04
proposed: 6230 · Software Subscriptions
reasoning: vendor "Adobe" + prior 11/12 months
confidence: 0.94
reviewer: M. Park (CPA) — approved 2026-06-05 09:12
posted to QBO

Per-firm pricing. No per-seat games.

Pick a tier by firm size. Add clients as you grow. Cancel anytime.

Starter

For solo CPAs and 2–3 person bookkeeping shops.

$750 /firm/month
  • 1 QuickBooks file
  • Up to 10 clients
  • Transaction Categorizer + Document Collector
  • Email support
Start free pilot
Most firms start here

Standard

For 5–20 person firms running CAS or bookkeeping at scale.

$1,500 /firm/month
  • Up to 5 QBO files
  • Up to 50 clients
  • All four workflows
  • Slack + email channels
  • Priority support
Talk to us

BYO Model

Bring your own LLM keys. For firms with data residency or model preferences.

$2,500+ /firm/month
  • Unlimited QBO files
  • Unlimited clients
  • Your Claude / OpenAI / Azure keys
  • SSO + admin controls
  • Named account contact
Contact sales

Bring Onsen to your firm.

We're piloting with a small group of US CPA and bookkeeping firms this quarter. Tell us about your firm and we'll be in touch within a business day.

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