Does a DBA need an EIN number?
If you just registered a DBA for your sole proprietorship, and you have no employees, you can use your Social Security Number as company tax ID. However, if the DBA is for a registered company like LLC or corporation, or if you have employees, then you must obtain EIN.
Many bankers would request an EIN regardless, because they are used to it. You can either try to educate them, or just obtain EIN, even though you are not required to.