Yes.  You can have up to 2 Accountant User on each company file.  Accountant users do not count towards the normal user limit and all users can be logged in doing work at same time.  Here is the breakdown by plan.

 

SimpleStart = 1 billable user + 2 accountant users

Essentials = […]

Resolution for 'clients admin issue: 'Can more than one user be active in QuickBooks Online at the same time? It would be my clients admin user and myself (accountant user).' available: Yes.

The clients admin issue or error code is a known issue in Quickbooks Online (QBO) and/or Quickbooks. Support for this issue is available either by self-service or paid support options. Experts are available to resolve your Quickbooks issue to ensure minimal downtime and continue running your business. First try to resolve the clients admin issue yourself by looking for a resolution described in the article. If it is a complex clients admin issue or you are unable to solve the issue, you may contact us by clicking here or by using other clients admin support options.

For more information about resolving issues related to clients admin in Quickbooks/QBO or to get support for the issue 'Can more than one user be active in QuickBooks Online at the same time? It would be my clients admin user and myself (accountant user).', click the link below: