Can I change a setting so that the email to my client doesn't show a due date for an estimate?

Hello there, info-elevatedsto.

Please note that you can customize the template for the estimate to remove the due or expiry date. However, this process won't affect when emailing the transaction to a client, and the information still displays when the person receives the email. With this, I'll ensure you can send feedback so your suggestion is forwarded to the Product Development Team.

I encourage you to submit feedback by going to the Gear icon regarding the ability to remove the due date when emailing the estimate to a client.

Here's how:

1. Choose Feedback under the Profile column.
2. Enter your comments or product suggestions. 
3. Click Next to submit feedback.

Once done, your recommendations are sent to our engineer for consideration in future updates.

In case you need steps on how you can turn an estimate into an invoice depending on the layout you have, you can read this article: Convert an estimate into an invoice in QuickBooks Online.

Don't hesitate to post again or leave a comment in this thread if you have further questions about managing estimates in QuickBooks. I'm more than willing to assist, info-elevatedsto. Take care always.