We offer two types of commercial accounts; a basic business checking for smaller volume and a commercial business account for larger volume customers. Does anyone know of any reason that we would not be able to open a basic business account for a DBA using a social security number? We have a customer whose accountant instructed them to open a business account so they do not really want a personal checking account that DBA's are entitled to.

Legally a d/b/a is allowed to use a social security number as their TIN; at their option they may instead apply for a EIN. I of course do not know what sort of Bank policy you may have, but short of that there is nothing wrong with a social security number (assuming it is the owner's of course).

We have an entrepreneur type account for sole props and D/B/A's and we do allow them to use thier TIN if they wish so I see nothing wrong with what you're saying.

Whether a given account for a sole proprietor is a personal account or a business account is really a matter of bank policy and/or agreement of the parties. The accountant in suggesting his client open a business account is really saying "go open an account for your business that is separate from your personal account." The accountant probably doesn't care whether the account is set up as a personal or business account. He just wants the funds separate.

As suggested above, a sole proprietor can use either his/her own SSN or an EIN on bank accounts. The IRS prefers the SSN, since that's how the business's income is reported (on the individual's 1040).