I have an account called Checking-1. It has a negative balance and I don't know why.

I'm delighted to have you here today, brad. 

I'm here to share the cause of why you're seeing a negative balance on your bank accounts in QuickBooks Online (QBO).

In QBO, when your bank balance shows negative, it's usually a result of making payments or processing checks that contain a larger amount than the money you have in your checking account. If this is the case, what you'll want to do is to generate a report. Doing this allows you to track all transactions associated with your bank.

I'll input the steps below to get you going. Here's how:

1. Go to the Reports tab.
2. Open your Balance Sheet report.
3. Modify the reporting period.
4. Click the amount of the bank account that shows up as a negative number. It will pull up its transaction report.
5. Press the small Gear icon.
6. Click anywhere to refresh the page.

After running the report, review all the money-out transactions and determine what's causing the negative balance.

In addition, here's an article about modifying reports and adding more details to it: Customize reports in QuickBooks Online.

I'll be more than happy to help you if you need further assistance with this, brad. You can mention me in the comment section below. I'll make sure to get back to you right away. Stay safe!

It has a negative balance because the outflows are greater than the inflows.  Basically, the ~checks written are greater than the ~deposits.

You can view the activity in the account register to see if that's correct. Also, if you reconcile the account regularly, then you'll know that the activity in the account is appropriate.