This depends on your situation. If your business will operate under the name of your LLC, that satisfies the requirement from the bank (although many banks also require an EIN or Federal Tax ID).

If however, you operate under a different business name than your LLC, you will need a DBA (or Trade Name as it is called in Colorado) to transact business under that name.

Example: You file your LLC for “Vicky’s Baked Goods, LLC” and that is the name of your store and your bank account. The Articles of Organization (LLC filing paperwork) take the place of a trade name/DBA.

If however, you want to operate the business as “Baked Delights”, you would need a DBA.