Topic: ACCTID, what can it be used for

I am new to OFX and I wanted to know how important the format of the ACCTID is within an OFX file. I was under the assumption that the ACCTID was simply a key to uniquely identify each account.

However, from my understanding when it comes to financial institutions the ACCTID should be the actual account number because some customers (especially commercial) use this number for conciliation, and to produce documents which uses the customer’s bank account number.

Is this the case? If so, what can the different accounting software do with the ACCTID in their daily operations?

Hope my question was clear.

Thanks for your help in advance.

Re: ACCTID, what can it be used for

Some banks, e.g. USAA require zero-filled to a certain length.  For example, if your account is 12345 and they require 10-digits, you should send 0000012345.