Hi

500 lines is a walk in the park so to speak considering the latest
versions of Excel have around a million rows...

What would make the whole process smoother would be to have another
column with some other type of reference, like an invoice number or similar.

I assume you are downloading your bank statement? does it allow you to
add or remove specific fields, and is it in some delimited form.

There should be a reference field which you could get anyone making
payment electronically to use this purely for the purpose of the
invoice/ reference number.

Then, in your accounting system, make sure the same Invoice number is
attached to that specific ledger entry.

you can then run a Find/Match using VB, anything that does not match
will highlight and you can then go and manually check why.

HTH
Mick.