Hi Holly,
Great question! I just checked mine and I remember my business was listed under Accounting services at one time but I had an issue with Quickbooks so I changed it to Social Advocacy organization (which is how I started my business before I found AADMM). In looking it over now, I agree with Yvonne that the 541219 seems to fit.
I’m also curious what others are using. Here’s the info from the NAICS site.
541219 541219 541219 Accountants’ (except CPAs) offices
541219 541219 541219 Accountants’ (except CPAs) private practices
541219 541219 541219 Accounting services (except CPAs)
541219 541219 541219 Billing services
541219 541219 541219 Bookkeepers’ offices
541219 541219 541219 Bookkeepers’ private practices
541219 541219 541219 Bookkeeping services
541219 541219 541219 Medical coding services combined with accounting services (except CPA services)