Mitsui Sumitomo and Lloyds Bank (among others, I presume) use 7 digit bank account numbers. It seems that if they have more that 9,999,999 customers, they wouldn't be able to route transactions to the new ones.

While I couldn't find an exact figure for the number of customers this page indicates that Lloyds Banking Group (of which Lloyds Bank is the foremost member) has 30 million customers. Furthermore, Mitsui Sumitomo is, AFAIK, the largest bank in Japan. Japan has a population of 120 million, meaning that if Mitsui Sumitomo has a 10% market share it would have more customers than account numbers.

How do they get around this?

  • 3
    Multiple SWIFT codes? (In the US, I know that Chase Bank has a different routing number for each state it has branches. New York State even has two routing numbers.)
    – RonJohn
    Commented Nov 6, 2019 at 15:11
  • @RonJohn Looking at Japan Bank Directory, it looks like at least Mitsui Sumitomo uses the same SWIFT code for all branches. I know I do have to provide my branch number to log in to online banking though, so maybe that's along the right lines.
    – Omegastick
    Commented Nov 6, 2019 at 16:56
  • 1
    Do they perhaps just omit the leading zeros? E.g. when I log in to my credit union's web site, my account number is 4 digits. On checks and other places (like IRS electronic payments) those 4 digits must have 12 leading zeros.
    – jamesqf
    Commented Nov 6, 2019 at 17:35
  • 3
    I'm voting to close this question as off-topic because it is not about personal finance and money issue that the OP is facing. Commented Nov 6, 2019 at 17:38
  • @DilipSarwate Which site should this be posted on?
    – Omegastick
    Commented Nov 7, 2019 at 1:39

1 Answer 1


In the UK, Lloyds use Sort Codes AND account numbers to identify a specific bank account.

Lloyds have the Sort Code Range of 30-00-00 to 39-99-99 available, so they have enough codes for everyone on the planet to have 10 accounts.

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .