In a few steps, I'll show you how to categorise banking transactions in QuickBooks Online, @SteveGHO.

Once the transactions are uploaded, QuickBooks sends downloaded transactions to the For review tab. Review them one by one.

Then, you can choose to split or consolidate payments. Please follow the instructions below:

1. Go to the For review tab.
2. Select the downloaded transaction to expand the view.
3. If the option in the Action column is Match, change the Find match to Categorise.
4. Select the Split tab next to the Add button. In this manner, it opens the Split transaction window.
5. From the Category dropdown, choose the categories (the accounts) you want to split.
6. Enter an Amount for each.
7. Select a Customer.
8. Press Apply and accept once done.

Furthermore, if you need to change or move a transaction to a different account, follow these steps to undo or un match it. Then 

When everything is in place, I have this article that will help you organize your accounts seamlessly: Reconciling account in QuickBooks Online.

I'll be right here to support your growing business. If you need assistance reconciling your accounts, you can tag me anytime.