Let me chime in and share some information, JenAufrecht.

Assigning transactions to the correct accounts will depend on how your bank handles downloaded transactions. If your bank downloads the transactions to a single account, you can only connect the parent account in QBO.  

Since assigning the correct subaccounts will depend on your transactions and the downloaded information, you can check and change its category within your Bank Transactions menu.

Here's how:

1. From the left navigation panel, click the Transactions menu.
2. Choose the Bank Transactions.
3. If it's already categorized, go to the Categorized tab.
4. You can see the category of each transaction under the Category column.

If you want to change the category of your transaction, please compare it first to your bank statement. Afterward, if you're certain that you need to change its category, you can follow these steps:

1. From the left navigation panel, click the Transactions menu.
2. Choose the Bank Transactions.
3. Go to the Categorized tab.
4. Find the transaction, then click Undo.
5. Press the For Review tab, then select the transaction.
6. Tap the Categorize bullet.
7. From the Account dropdown, choose your preferred category.
8. Once done, click Add.

You can also create a bank rule to categorize the transactions from your bank automatically. You can follow these steps:

1. Go to the Gear icon in the upper right corner and choose Rules.
2. Press New rule.
3. From the What do you want to call this rule?, enter the name you prefer for your rule.
4. Enter the necessary details according to your preference.
5. Once done, click Save.

I'll leave this material for you to learn more about bank rules: Set up bank rules to categorize online banking transactions in QuickBooks Online.

Afterward, you can categorize online bank transactions in QuickBooks Online.

We'll be around to help whenever you need us. Just let us know in the comment section.