US Checking Account data validation

Does anyone know where I can find simple US Checking Account data validation rules online? I’m just looking for level 1 non-database based validation. I have the rules for routing numbers; I don’t need that. But, the only rule I know for sure is that the account number cannot be longer than 17 digits.

The terminology I’ve found for these numbers are Transactional Account, Demand Account, and Direct Demand Account. Again, only for use within the United States of America.

In searching the Web for answers, I get the sense that there’s some sort of check-number that can be verified using modular arithmetics. What is the minimum length for an account number? I found info using sort codes, but that’s for UK-based checking accounts. For my purpose, I’m only using US-based checking/savings account numbers.

I am not looking to verify that a checking account exists, is active, nor has funds. The real problem I’m trying to solve is that our company accepts these accounts over the phone and a large percentage of call center agents are making errors that the company is liable for. I’m just trying to reduce these costly errors greatly.

Thank you in advance,

-=- PalaDolphin

From a quick search on the net, the answer seems to be ‘whatever the company in question wants to use’… but 8 seems to be the default length; ACH specifications state that the combined Routing+Account number not exceed 17 characters; a routing number is 9 digits long, leaving 8 for the account number; and 8 digits would give the greatest random possibilities of account numbers. (You dont really want to assign accounts incrementally…)

Is it a hard and fast rule? no.

My TCF Bank account# alone is 10 digits.

Odd. TCF must use a different system for ACH transactions, then, because the structure seems to be fairly set.

Ironically, I think it would be easier to use a payment gateway to verify that a checking account exists, is active and has funds than to take a guess on the length of the routing numbers.

One major problem is these standards change periodically. Second, I would guess that gathering and storing checking account information without certification is a major liability in and of itself. I know this is the case with credit cards, with a possible fine around $500,000 per number if your system is breached and credit card numbers are stolen. Again, I don’t know if electronic checks are subject to the same scrutiny, but my instinct tells me they are and if I were you I’d be researching the legal ramifications of what your company is requesting to make sure that you aren’t subject to personal liability in the case of a breach.