You're overpaying your vendors. We find where and fix it.
FairBill reviews your past and incoming vendor invoices, catches billing mistakes and overcharges, and handles getting them corrected with your approval. Start with a free review.
The first review is free, with no commitment to ongoing monitoring. No vendor is contacted without your approval.
Billing mistakes.
Real money.
Duplicate charges, incorrect rates, and missing credits can slip through even well-run finance teams. And when you're dealing with dozens of vendors every month, checking every invoice becomes a job of its own.
Of surveyed US mid-market finance leaders in hospitality, retail and healthcare reported invoice fraud or overpayment in the past year.
Ottimate and NewtonX survey, Feb 2026Estimated yearly leakage from duplicate payments, invoice errors, missed credits and fraud at large UK and US firms. Extrapolated from Xelix customer data.
Xelix Financial Leakage Report, Feb 2026Average invoice exception rate across AP departments, creating additional investigation and follow-up work.
Ardent Partners, State of ePayables 2025Industry figures from the sources linked above, not FairBill results.
You stay in control.
Your approval first.
Nothing goes to a vendor until you approve it, and you choose which findings to pursue.
Evidence with every finding.
Each one shows the invoices and records behind it, where they exist.
Flagged isn't proven.
A higher price can be fair. We say what's confirmed and what needs a contract to check.
Your data stays yours.
Read-only access to your accounting and inbox. Stored in the EU and deleted on request.
Billed 18% more than March
Waiting for your approvalPromised credit never applied
NewSame invoice paid twice in February
Sent to vendorVolume discount not applied since June
Corrected
Billed 18% more than March, with no change in service.
$628/moto checkSame service on both. No agreement on file yet, so we ask the vendor before calling it an error.
Hi, our April invoice for waste collection is 18% higher than March with no change to our service. Could you confirm the reason, or correct it to the March rate? Thanks.
Nothing is sent until you approve.
How it works
The free review looks back over your past invoices. Monitoring is the ongoing service that checks every new one as it arrives.
- 01
Connect your invoices.
Connect your accounting or billing inbox, or forward invoices to your FairBill address. Add any agreements you have. That's all we need to start.
- 02
Get your free review.
Our AI agents go through your past invoices, flag possible discrepancies and back each finding with evidence.
- 03
We help get it fixed.
You review the findings and approve next steps. We contact the vendor, request the correction and follow up where we can.
- 04
Stay covered.
We keep checking every new invoice for mistakes, unexpected changes and issues that are still open.
Xero
Zoho Books
Outlook- Email forwarding
What we look for
We check recurring vendor and supplier bills of any kind. What we can confirm depends on the invoice and the records you share, so each finding says what it is based on.
Start with a free review.
Find out what might be hiding in your vendor bills. FairBill reviews your past invoices to uncover potential billing errors, overcharges and missed credits. No commitment required.
Book your free review- 01We go through your past vendor invoices.
- 02You get every finding, with the evidence behind it.
- 03Continuous monitoring is the next step, if you want it. We share its terms before you enroll.
- 04If you stop after the review, you owe nothing.
Questions
What does FairBill check?
Your past and incoming vendor invoices. We look for duplicate charges, billing errors, unusual price changes, missing credits and charges that don't match the agreements you share.
Does FairBill work with any industry?
Yes. It's built for any business that gets vendor invoices regularly. Which checks we can run depends on the type of invoice and the records available.
What happens when FairBill finds an error?
We investigate, gather the evidence and prepare a correction request. With your approval, we send it to the vendor and follow up until it's resolved.
Will FairBill contact vendors automatically?
No. Nothing goes to a vendor until you approve it.
What access does FairBill need?
Read-only access to your accounting software or billing inbox, or no access at all if you forward invoices to your FairBill address. FairBill never makes payments or changes your accounting. Your data is stored in the EU, and we delete it when you ask.
Is the first review free?
Yes. The review of your past invoices is free. Ongoing monitoring is a separate service, and we share its terms before you enroll.
Does FairBill replace our accounting software?
No. It works alongside your current tools, checking vendor bills independently and helping resolve what it finds.
Find out what you're overpaying.
Start with a free review of your past vendor invoices. We send back what we find, with the evidence behind each finding.
We reply within a business day to set up a short call. Everything is agreed in writing before we start.