Is there a way to add further CIS information on to a CIS invoice?

You've come to the right place, @roger-wilson.

Yes, you can add CIS information to an invoice. Let's first enable the CIS feature in your account. I can guide you how to do it.

1. Go to the Gear Icon.
2. Choose Account and Settings.
3. Click Advanced.
4. Put a checkmark on the Construction Industry Scheme (CIS) tickbox. 
5. Enter your info.
6. Click the Save button.
7. Hit Done. 

Once completed, here's how to set up the customer as a CIS contractor:

1. Go to the Sales menu.
2. Choose the Customers tab.
3. Select the customer, then click to open the profile.
4. Click Edit.
5. Tick the Is CIS contractor box, then click Save. 

Once you create an invoice, the CIS deduction will automatically pop-up. You'll just have to enter the rate so our program will automatically calculate the deduction.

Always feel free to leave a post below if you have other questions. I'm always here to help.