Only if someone asks you to fill out a W9. I was able to enter my info directly into the IRS form on my computer and save it filled out so I have it ready to go if anyone asks me for it. Having a DBA doesn't matter unless you you set it up as a LLC S Corp or Partnership. If you are a sole proprietor or self employed for it you just file the DBA on your personal 1040 return using Schedule C.
