Greetings, @carla45. It is a pleasure to see you in the Community forum. I am pleased to offer my insights on modifying pay schedules in QuickBooks. By doing so, you will be able to allocate the new schedule to your employees in a timely and efficient manner.
There are no additional costs associated with changing the pay schedule from twice a month to biweekly using QuickBooks. To make the change, you will need to update the pay schedule and assign it to your employees. By following these steps, you can ensure that your payroll system is up to date and that your employees receive their pay on time.
To set up, assign, and update a pay schedule to your employees, follow the steps below:
- Go to Payroll, then Employees.
- Choose your employee.
- From Employment details, select Start or Edit.
- From the Pay Schedule ▼ dropdown, select the pay schedule for the employee moving forward. Or, to create a new pay schedule, select + Add pay schedule.
- Fill out the appropriate fields. Then pick Save.
- Select Save.

If you want to edit the pay period, you must select or enter the correct pay period ending. For more details, on setting up payroll schedules, see this article: Set up and manage payroll schedules.
I'll be dropping some articles that will help you create paychecks and run payroll automatically on QuickBooks Online Payroll:
Please let me know about any updates in the comments section below. If you require any further assistance regarding payroll concerns or have any queries related to pay schedules and periods in QBO, please feel free to reach out to me. Stay safe.