What is modulus checking?

Modulus checking validates UK bank account numbers using mathematical algorithms (Mod 10, Mod 11, Double Alternate) to detect errors and prevent payments to invalid accounts. It's required for UK payment schemes including BACS, Faster Payments, and CHAPS.

What is Confirmation of Payee (CoP)?

Confirmation of Payee (CoP) verifies that the account name matches the account details before making a payment. It helps prevent fraud and misdirected payments by checking if the name on the account matches what you expect.

How much does eSortcode cost?

Modulus checking starts from 1.9p per check on monthly volume (2.4p at 10,000 checks/month). Confirmation of Payee from 15p per check. BACS Bureau has flexible credit-based pricing. Enterprise SLA is £99/month with 99.9% uptime.

Since 2006 · ISO 27001

UK bank account validation and BACS Bureau services

Priced in pence. In production for twenty years.

Start free Try a check

Modulus from 1.9p · CoP from 15p · 50 free credits, no card.

Modulus check Example

Sort code: 09-01-28
Account: 12345678
Result: Valid
Bank: Santander UK plc
Time: 14 ms

{ "valid": true, "algorithm": "MOD11" }

Used across UK payments

Three services. One bureau.

Validate the number, confirm the name, submit the file.

Modulus checking From 1.9p Sort code and account number, BACS-approved algorithms. Details →
Confirmation of Payee From 15p Does the name on the account match before you pay. Details →
BACS bureau From 20p Direct Debits and Credits, with KYC on the way in. Details →

Pricing

No setup fee. No monthly minimum. Volume is automatic.

Service	From	At 10,000 / month
Modulus checking	1.9p	2.4p	Calculator
Confirmation of Payee	15p	Volume on request	Calculator
BACS bureau — new mandate	20p	Collections included	Calculator

Annual modulus packs still apply at higher unit rates. EISCD extracts are priced separately. All + VAT.

Need a 100% uptime contract on modulus and CoP? Enterprise SLA is £99 a month.

Enterprise SLA →

Open an account.

Fifty free checks. No card. The same API the bureau has run since 2006.

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ISO 27001 · ISO 9001 · Vocalink data partner