Hi there,
The opening balance tells QuickBooks Online when you want to start tracking transactions in an account. It's also an important reference for reconciliations. The opening balance in QuickBooks Online needs to match the balance of your real-life bank account for whatever day you pick. I'd be glad to help shed some light on this for you.
If the opening balance is off, don't worry. Here's how to fix so you can start reconciling. Follow the section depending on if this is your first time reconciling the account: Fix opening balance issues in QuickBooks Online.
This helpful article should help you get back on the right track. If you're still in need of further assistance after reviewing it, please don't hesitate to reach out to our tech support team for one-on-one help. You can contact us here: Get in touch.
If there's anything else I can do to help, let me know.
Have a great day!