I have my bank account connected to QBO which I now receive cashback rewards into my bank. How do I properly log these transactions? (as it's not income)

Hi there, Aaron.

To properly record your cashback in QuickBooks Online (QBO), follow the steps below.

1. Navigate to the + New button.
2. Click on Credit card credit.
3. Choose the correct account from the Bank/Credit Account drop-down box.
4. Under the Category details, select the account that you have for your cash back rewards whether expense/income account as you see fit.
5. Fill in the other necessary information.
6. Select Save and close.

For additional information, check out this article: How can I record a cash back to my credit card account?

If you're unsure about which account to use in the category details, I recommend consulting your accountant to determine the appropriate account.

Moreover, I've included an article that'll help match your QuickBooks account and bank statements: Reconcile an Account in QuickBooks Online.

Feel free to visit the Community again if you have other concerns about cashback in QuickBooks Online. We're always here to help.

@aaron-bg 

"Technically the cashback is from expenses paid for on the credit card so it's not income. But it increases the balance of the checking account..."

Actually, it is income.  Record it to an 'Other income' account so as to differentiate it from income from your primary operations.