When you've already paid your employees prior to purchasing the system, you'll have to enter their past pay details (wages, deductions, and taxes) into your QuickBooks Online (QBO) Payroll account. This is to make sure everything is accurate for year-to-date (YTD) totals on your employees’ pay stubs. With this, you're able to report correct W-2 information at the end of the year. You can complete this process through the Payroll menu's Overview tab only if you haven't created any paychecks for your employees yet.
Once you've already created paychecks, I'd recommend contacting our Payroll Support team. They can securely pull up your account and enter your prior payroll history. In case you want to talk to one of our representatives, you'll have to request a callback. They're available to assist you from Monday to Friday, 6:00 AM to 6:00 PM PT. Here's how:
Go to the Help menu.
Choose Contact Us.
Enter your specific concern in the What can we help you with? box.
Click Let's talk.
Select Get a callback.
Enter your contact details.
Click Confirm my call.
I've attached a screenshot below for your reference.
Additionally, there are several payroll reports in QuickBooks that you can view to get a closer look at your business's finances and employee information. For the complete list, you can check out this article: Run payroll reports. It also includes steps about printing, customizing, and marking them as your favorite.
Please know that you're always welcome to comment below if you have other concerns or follow-up inquiries about managing your payroll account and employees' pay information in QBO Payroll. I'm just around to help. Take care.