How can we sho the "TRN" number from "Account and settings on our invoice forms?

Welcome to the Community forum, Mike. It's good to see that you've finished adding the TRN in the Account and Settings section. Let me guide you on how to display this on your invoice form.

To display the TRN on the invoice form, you need to edit the Custom Form Style and add it in the Company Registered Number (CRN) section. Here's how:

1. Click the Gear icon.
2. Select Custom Form Styles from the Your Company column.
3. Look for the default invoice style you used and click the Edit icon below the Action section.
4. Pick the Content option.
5. Then, click the first box on the right side.
6. Tick the box of the Company Registration Number (CRN). Then, enter your TRN there.
7. Click Preview PDF to see if the TRN is shown in the form.
8. Once done, click the X icon of the sample PDF. Then, click on Save. 
   
   

For additional details, you can read this article: Customise invoices, estimates, and sales receipts in QuickBooks Online.

Please know that this field won't show when entering an invoice transaction. It's only visible once you view the PDF version by clicking the Print or Preview tab and/or when sending it to your customer by opening the attached PDF in the email.

If you wish to view the TRN field while creating an invoice transaction, you can add it as a custom field. However, you'll need to enter the number manually. Check out this article for more information: Add custom fields to sales forms and purchase orders in QuickBooks Online.

You might want to learn how to update the basic information of your business that displays on your sales forms. Feel free to visit this article: Change your company name, contact information, or Business ID No in QuickBooks Online.

Don't hesitate to return here if you have additional questions about managing the display of your invoice form. We'll be more than happy to help. Take care, and enjoy the rest of your day.