How can I edit a customer invoice

[WHMCS John]

Hi all,

Thanks very much for your feedback on the invoice immutability and credit/debit notes implementation in v9.0.

We heard you loud and clear, and I'm pleased to say that in v9.1 we have implemented an admin-configurable Invoice Immutability setting. You can enforce invoice immutability, relax it while keeping billing notes, or turn it off entirely.

For more information check out our release highlights, try it out yourselves, and share your feedback in the v9.1 Beta Discussion Board

[LittleCreek]

6 hours ago, WHMCS John said:

Hi all,

Thanks very much for your feedback on the invoice immutability and credit/debit notes implementation in v9.0.

We heard you loud and clear, and I'm pleased to say that in v9.1 we have implemented an admin-configurable Invoice Immutability setting. You can enforce invoice immutability, relax it while keeping billing notes, or turn it off entirely.

For more information check out our release highlights, try it out yourselves, and share your feedback in the v9.1 Beta Discussion Board

Thanks so much John. 

[LMG]

7 hours ago, WHMCS John said:

Hi all,

Thanks very much for your feedback on the invoice immutability and credit/debit notes implementation in v9.0.

We heard you loud and clear, and I'm pleased to say that in v9.1 we have implemented an admin-configurable Invoice Immutability setting. You can enforce invoice immutability, relax it while keeping billing notes, or turn it off entirely.

For more information check out our release highlights, try it out yourselves, and share your feedback in the v9.1 Beta Discussion Board

Thank You!!

[robinson12]

The invoice immutability change definitely makes simple corrections more complicated. I can understand keeping an audit trail, but having an easy way to issue a corrected invoice without manually rebuilding everything would make the process much smoother.

[Patty]

That's great news! It should be optional indeed! Thanks, John! 🙌

[Eugene]

On 10/7/2026 at 5:40 PM, WHMCS John said:

Hi all,

Thanks very much for your feedback on the invoice immutability and credit/debit notes implementation in v9.0.

We heard you loud and clear, and I'm pleased to say that in v9.1 we have implemented an admin-configurable Invoice Immutability setting. You can enforce invoice immutability, relax it while keeping billing notes, or turn it off entirely.

For more information check out our release highlights, try it out yourselves, and share your feedback in the v9.1 Beta Discussion Board

woo, thank you so much 🙂