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Live direct connection, no aggregator in between

Your Mercury account,
doing its own books

Connect once with a read-only API token. Your USD business account syncs automatically, incoming payments match your invoices and mark them paid, and your accountant Finn can check the bank whenever you ask.

Connect Mercury

Read-only token · your keys, encrypted · disconnect any time

AccountsOS connects directly to Mercury via a read-only API token you create yourself, your accounts and transactions sync automatically, and incoming payments reconcile against invoices without any manual matching.
accounts-os.com/banking
Mercury · Business USDSynced
Stripe payout
+$4,200.00
Income
AWS
-$88.10
Software
Notion
-$16.00
Software
FPulled 34 transactions and categorised them.

A payment arrives. Everything else just happens.

This is the loop other tools make you run by hand: import, code, match, mark paid. Here it runs itself.

01

Payment lands in Mercury

A customer pays an invoice into your Mercury business account.

02

It syncs into your books

The direct feed pulls it in every morning, or the moment you ask Finn to check your bank.

03

Finn categorises it

AI coding with your company context and your own bank rules applied first.

04

The invoice flips to paid

Reconciliation runs automatically, confident matches apply, your ledger posts, and you get a 'done' message. Exceptions wait for one-tap review.

Finn, your AI accountant

Chat to your bank. Literally.

Finn is connected to the feed. Ask in plain English and he pulls fresh transactions from Mercury on the spot, then reconciliation follows automatically.

  • "Has the payment from Acme landed yet?"
  • "Check my bank and reconcile anything new."
  • "What's my Mercury balance?" (the real one, as your dashboard reports it)
  • "What did we spend with AWS this month?"
Finn, has the $4,200 Stripe payout landed?
Just checked your Mercury account, yes, $4,200 from Stripe landed 18 minutes ago. I've matched it to invoice INV-0031 and marked it paid. Your USD balance is $28,940.
Nothing else needs you, AWS and Notion came out in the background and they're categorised already.

Read-only, by design

The token you create only grants read access. AccountsOS can see accounts and transactions but can never move your money. Revoke it in Mercury any time.

Your token, encrypted

The API token belongs to your company. It's stored AES-256 encrypted and never appears in logs, disconnect from AccountsOS whenever you like.

Built for startup finances

USD accounts, Stripe payouts, vendor spend, the categories and reports are shaped for how a Mercury-banked company actually spends money.

Mercury tells you what moved. Finn tells you what it means.

Mercury is where startups keep their runway, AccountsOS is where that runway becomes real books: categorised spend, reconciled invoices, tax figures, and a P&L you can actually read. Finn watches the account so you don't have to open a spreadsheet to find out how the business is really doing.

Money moves in MercuryFinn categorises + reconcilesRunway and reports stay current

Frequently asked questions

How does AccountsOS connect to Mercury?

Through a personal API token you create yourself at mercury.com/settings/tokens. You paste it into AccountsOS once, we validate it against Mercury and store it encrypted. No OAuth redirect, no aggregator in between, just Mercury's own API.

Is the connection read-only?

Yes. The token you generate is read-only, AccountsOS can see your accounts and transactions but can never move money, add a payee, or send a payment. The token is stored AES-256 encrypted and you can disconnect or revoke it from either side at any time.

Does it reconcile payments against invoices automatically?

Yes. Every sync that brings in new transactions automatically dispatches a reconciliation run. Incoming payments are matched to open invoices and marked paid, spending is matched to receipts and bills, and confident matches post to your ledger. Anything ambiguous waits in a review queue, you only see exceptions.

Can I ask Finn about my Mercury account?

Yes. Ask Finn 'check my bank', 'has the payment from Acme landed?', or 'what's my Mercury balance?', Finn pulls fresh transactions on demand and reads back the balance your Mercury dashboard shows, not an estimate.

What balance does AccountsOS show?

The balance Mercury reports, the same figure as your Mercury dashboard. Statement-upload accounting tools can only show a running total of imported transactions; a direct feed shows the real number.

Can AccountsOS send payments from Mercury?

No. The connection is read-only by design, AccountsOS never initiates a transfer or payment from your Mercury account. Payments still happen in Mercury itself; AccountsOS just makes sure they're booked correctly once they do.

Do I need a specific Mercury plan?

No. Personal API tokens are available to any Mercury account. The connection itself is free in AccountsOS, it's included as a connector on every plan.

Why pair Mercury with an AI accountant instead of just using Mercury's own dashboard?

Mercury shows you the money moving, AccountsOS turns it into books: categorised transactions, reconciled invoices, VAT/tax figures, P&L and balance sheet, all without you touching a spreadsheet. Founders on Mercury still need real accounts, Finn is the accountant that keeps them current automatically.

Five minutes to connect. Then it's Finn's problem.

14-day free trial, then £20/month. The Mercury connection is included on every plan.

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Already a customer? Connect from Settings → Integrations