Hi there, MEL7111.

When reconciling accounts, it can only be done on a single company. That said, you'll have to reconcile the accounts of the first company and then do the same on the other company.

You can check these references as your guide:

• How to Reconcile an Account in QuickBooks Online.
• Fix issues the first time you reconcile an account in QuickBooks Online.

I'll be around if ever you need help. Keep safe!