New client hasn't claimed employers allowance for earlier years didn't use QBO for the periods.

Hello there, catch.

Welcome to the Online Community. Let me guide you in the right direction in recording your client’s employment allowance.

Currently, QBO will not allow you to enter previous payroll information. You’ll have to process them directly to the HMRC.

For the current year, you’ll have to set up the Employment allowance in QuickBooks. 

1. Go to Employees on the left panel, then choose Set up your payroll.
2. Select Start next to Claim Employment Allowance credit.
3. Go the Account and Settings page, then click Payroll on the left panel.
4. Select Yes for Does your business qualify for Employment Allowance.
5. Click on Save.

Please know we generate an EPS filing and the state that you’re eligible in the Employment Allowance Indication. If you have already informed HMRC that you qualify, do not send the tax

For more insights about the filing process, proceed to Step 2 in this article: Set up Employment Allowance.

he information I provided should help you moving forward.

If you have further questions about payroll, leave me a comment by clicking on the Reply button. I’ll be right here with you. Have a good one.