Hello Jon1, 

Thanks for reaching out to us on the Community page, 

When selecting NO VAT as a tax code it should not be hitting any of the boxes at all. The link below shows you which vat codes hit which box.  Could you seen us a screenshot of your not vat hitting box 7 so we can have a look into this for you. Thanks 

https://quickbooks.intuit.com/learn-support/en-uk/vat/common-vat-codes/01/239529