Yes, you can save you invoice without entering an email address. Just be sure you don't select the Save and Send option so you won't be required to enter an email address.
You can always post back here when you have additional questions.
Hi. I don't have this as an option on my screen and it keeps saying add valid email address. I just can't seem to work out how to create a valid invoice without having to send it somewhere. Any tips please?
I've encountered the same situation before, suz3.
You'll get this error when the Send later box is checked under the Customer email field. Let's change the preferred delivery method by following these steps:
Here's a sample screenshot for reference:
You can also go to the settings to set the delivery method.
That should fix the error when you save the invoice.
If there's anything else you need, you can always leave a reply on this thread. Have a great day!