I want to turn off one specific autofill for the account field

Hi there, 123joan321.

Thanks for dropping by here in QuickBooks Community. Allow me to help and address your concern, so let me get this straightened out. 

Currently, there's isn't an option to turn off the specific auto fill for the account field in QuickBooks Desktop Mac. I can see how this future would be helpful for you, I recommend sending feedback directly to our product developers for consideration in the future updates. 

Here's how you can send feedback: 

1. From the QuickBooks menu, click QuickBooks Feedback.
2. Select Product Suggestions in Type of feedback section.
3. Fill out the necessary information and click Send Feedback. 

For future reference, you can always check this article: QuickBooks Desktop for Mac 2019 User’s Guide.

You're always welcome to post if you have any other questions. We're always here to help you out. Have a good one. 

You can turn off autofill though for all fields. 

Also if you tab to the field it will be selected and when you type it will be replaced.

The problem is that when QuickBooks autofills a split transaction.  A user then finds themselves having to delete various multiple lines of split entries.

Hi there, richarducla.

Welcome to the QuickBooks Community. I'll make sure to share some information on how users in QuickBooks Desktop for Mac works.

In QuickBooks Desktop for Mac, you can set the user and password preferences. This way, the users can only access what's needed for their role. That said, I suggest changing or editing the user's rights to restrict access to certain areas in QuickBooks. That way, the said user will be unable to delete the split entries in your account.

Here's how:

1. Select Company. Then, Users and Passwords.
2. Double-click the user name and make your adjustments.
3. Close the Preferences window when done.

For additional information, you can click this article: User and password preferences in QuickBooks Desktop for Mac.

Please refer to this article to view different details on how to modify, fix common issues, and unexpected results with renaming rules for Bank Feeds in QuickBooks Desktop: Use renaming rules for Bank Feeds.

You’re always welcome to get back to me if you have other follow-up questions about users in your accounts. I’d be more than happy to assist you at any time. Take care and keep safe.