AI agents for business finance: what they can and can't do
What AI agents can do in bookkeeping, close, collections and compliance today, where a person must stay in charge, and how to judge a product.
The short answer
A NUBAN is the 10-digit account number every Nigerian bank account has used since the CBN introduced the standard in August 2010. The first nine digits are a serial number chosen by the bank and the tenth is a check digit, calculated from the bank’s 3-digit code and the serial using the weights 3, 7, 3 repeated, so a mistyped number can usually be caught before money moves.
NUBAN at a glance
- Full name
- Nigeria Uniform Bank Account Number
- Introduced by
- Central Bank of Nigeria (CBN), circular of 30 August 2010
- Check-digit rule published
- CBN circular “Check digit algorithm for NUBAN”, 27 April 2011
- Length
- 10 digits
- Structure
- 9-digit account serial number + 1 check digit
- Hidden input
- The bank’s 3-digit CBN code (not printed in the account number, but used in the calculation)
- Weights
- 3, 7, 3, 3, 7, 3, 3, 7, 3, 3, 7, 3 across 12 digits
- Modulus
- 10
Before NUBAN, Nigerian banks used account numbers of different lengths and formats, which made interbank transfers error-prone. NIBSS notes that the 10-digit scheme, introduced in August 2010, was one of the reforms that prepared the ground for NIBSS Instant Payment (NIP) in 2011. Today the same 10 digits are used for transfers, direct debits, salary files and name enquiry across banks, microfinance banks, payment service banks and mobile money operators.
How the check digit is calculated
The check digit is not random. It is derived from 12 digits: the bank’s 3-digit code followed by the 9-digit serial number. The steps are the same for every bank.
- Write the 3-digit bank code followed by the 9-digit serial number, giving 12 digits.
- Multiply each digit by its weight, in order: 3, 7, 3, 3, 7, 3, 3, 7, 3, 3, 7, 3.
- Add the 12 products together.
- Take the remainder when the sum is divided by 10 (modulo 10).
- Subtract the remainder from 10. If the answer is 10, the check digit is 0; otherwise the answer is the check digit.
- Append the check digit to the 9-digit serial. The result is the 10-digit NUBAN.
Worked example, digit by digit
Example only: a hypothetical serial number 012345678 at a bank whose CBN code is 058. The serial is invented for illustration and is not a real customer account.
| Position | Digit | Weight | Product |
|---|---|---|---|
| 1 (bank code) | 0 | 3 | 0 |
| 2 (bank code) | 5 | 7 | 35 |
| 3 (bank code) | 8 | 3 | 24 |
| 4 (serial) | 0 | 3 | 0 |
| 5 (serial) | 1 | 7 | 7 |
| 6 (serial) | 2 | 3 | 6 |
| 7 (serial) | 3 | 3 | 9 |
| 8 (serial) | 4 | 7 | 28 |
| 9 (serial) | 5 | 3 | 15 |
| 10 (serial) | 6 | 3 | 18 |
| 11 (serial) | 7 | 7 | 49 |
| 12 (serial) | 8 | 3 | 24 |
| Sum | 215 |
215 divided by 10 leaves a remainder of 5. 10 minus 5 is 5, so the check digit is 5 and the full NUBAN is 0123456785. If someone typed 0123456789 for the same bank, the calculation would expect 5 rather than 9 in the last place, and the number would fail validation.
Two more quick examples
| Bank code | Serial (example) | Weighted sum | Remainder | Check digit | NUBAN |
|---|---|---|---|---|---|
| 044 | 000000001 | 43 | 3 | 7 | 0000000017 |
| 011 | 300400500 | 46 | 6 | 4 | 3004005004 |
The same rule in code
In any spreadsheet or programming language the rule is one line of arithmetic: check = (10 − (Σ digit×weight mod 10)) mod 10. The second “mod 10” turns a result of 10 into 0. Developers often run it on every bank in a list to suggest which banks an account number could belong to, before calling a name enquiry service to confirm.
What the check digit can and cannot tell you
- It catches most single-digit typos. Changing any one digit changes the weighted sum, so the check digit no longer matches.
- It catches many swapped neighbouring digits, because adjacent positions often carry different weights (3 and 7). It will not catch every swap, for example two adjacent digits that both carry weight 3.
- It does not prove the account exists. A number can pass the check and still be unopened, closed or restricted.
- It does not identify the owner. Only a name enquiry, which banks run through NIBSS before a transfer, returns the account name. NIBSS describes name enquiry as the step that lets a payer confirm account details before a transaction.
- A number can be valid for more than one bank. Because the bank code is not printed in the 10 digits, the same NUBAN may pass the check for several bank codes. That is why you must always pick the bank as well as the number.
NUBAN for microfinance banks and other institutions
The original 2010 standard was written for deposit money banks with 3-digit CBN codes. Microfinance banks, payment service banks and mobile money operators are identified in the payments system by longer institution codes (public bank lists, such as the Paystack list used for our bank codes list, show 5- and 6-digit codes for many of them). Their customers still receive 10-digit account numbers, and the same weighting idea is applied over the longer institution code. If you are building validation for these institutions, use the current specification from NIBSS rather than the 3-digit version shown above.
Practical checks before you send money
- Copy the account number from a trusted source (an invoice, a verified message, the payee’s own app) rather than retyping it from a photo.
- Choose the bank carefully. A valid number at the wrong bank can resolve to a stranger’s name.
- Read the name your app shows after name enquiry. If it does not match the person or business you expect, stop.
- For large amounts, send a small test first. See our guide to bank transfer limits for the caps that apply by account tier.
How we put this together
The structure, introduction date and check-digit method come from the CBN’s NUBAN circulars of 30 August 2010 and 27 April 2011, as listed on the CBN circulars index, and from NIBSS’s published history of bank transfers. The CBN’s PDF server refused automated download on 17 October 2026, so the weights were cross-checked against our own calculations on the worked examples above. Bank codes used in the examples are as shown in the CBN-licensed bank list and the Paystack public bank list. Serial numbers in the examples are invented.
Questions people ask
How many digits is a Nigerian account number?
Ten. Every NUBAN has a 9-digit serial number chosen by the bank plus one check digit.
How do I know if an account number is valid?
Run the NUBAN check with the bank’s 3-digit code, then let your bank app perform a name enquiry. Only the name enquiry confirms the account exists and whose it is.
Can two banks have the same account number?
Yes. The bank code is not part of the 10 digits, so the same number can exist at different banks. Always select the correct bank.
What are the NUBAN weights?
3, 7, 3, 3, 7, 3, 3, 7, 3, 3, 7, 3, applied to the 3-digit bank code followed by the 9-digit serial number, with the result taken modulo 10.
Sources
- CBN: Nigeria Uniform Bank Account Number (NUBAN) circular, 30 Aug 2010 · accessed 17 Oct 2026
- CBN: Check digit algorithm for NUBAN, 27 Apr 2011 · accessed 17 Oct 2026
- NIBSS: From 3-day wait to per second transaction, how bank transfers work (Mar 2025) · accessed 17 Oct 2026
- NIBSS: Name Enquiry · accessed 17 Oct 2026
- CBN: Financial institutions (supervised categories and lists) · accessed 17 Oct 2026
- Paystack: List Banks API (public bank and institution codes, Nigeria) · accessed 17 Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.