how do you change the email cover letter for invoices

Hey there, @mybchw!

To clarify, are you referring to the email view when sending an invoice? 

Here's a sample visual reference below:

if yes, we can edit this on the Sales section under the Account and Settings. Here's how:

1. Click the Gear Icon at the top-right corner of QuickBooks Online.
2. Select Account and Settings under the Your Company section.
3. Click Sales from the left-hand menu.
4. Scroll to Online delivery and click the pencil icon.
5. Choose the options that suit your needs.
6. Select Save, then click Done.

However, if you are referring to something else, can you please provide a screenshot for us to give you accurate solution.

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