Can I change a profile to now start using account codes, where I have already entered transactions into accounts that were not set-up not using account codes?

Hello sdaly390,

Thanks for being a part of the QuickBooks Online family! It's awesome to hear that you've been using the product for a while and would now like to add account codes. From how you describe it, it sounds like you're talking about adding account numbers to your chart of accounts. If so, that's an easy set up! Here are the steps.

1. Go to the Gear icon in the upper right of your account.
2. Choose Account and settings.
3. Click the Advanced tab.
4. Click the pencil icon in the Chart of accounts section.
5. Check off the Enable account numbers box.
6. Click Save.

Once you've got that set up, you can then go and add account numbers to your chart of accounts. I've pulled those instructions from the following article: Use account numbers in your chart of accounts I recommend reading over the article as it also goes over how to assign account numbers to your accounts as well. It even gives suggestions of numbers you can use.

I hope that helps! Let me know if you have more questions. :)