Hello I am wondering if it is possible to set up a user for payroll access only in QBO as that is the only thing this employee would be doing?

The importance to streamline access for your team especially when you have an employee whose sole focus is payroll is a great factor for your business, RRtokai.

QuickBooks user roles allow you to customize permission so you will have the appropriate level of access based on your responsibilities. This helps maintain data security and make sure everyone has access only to the tools and information you need to perform.

However, QuickBooks Online (QBO) doesn't currently offer the option to assign a user with payroll-only access. 

To know more on assigning roles to people in QBO, check out this article for your reference: User Roles and Access Rights.

You can always comment below if you need additional help or have other questions with user roles or payroll. We're always around ready to assist you anytime as you wish.