Need to share billing access with sub-user

How do I share billing access to my sub-user responsible for managing payments

I am not sure what you meant by billing access? Are you referring to the Billing page in your account username irashidi?

Please note that you can only share forms and their submission data to sub-users, you cannot share any access to your account. Please note that sub-users are simply regular JotForm accounts. 

To learn more about sub-users and sharing forms, please check this guide: https://www.jotform.com/help/232-How-to-share-forms-with-a-sub-account-user. You could simply just share your login credentials to your sub-user and he/she could just directly login to your account and update the payment method in your Account->Billing page (if that's what you are trying to achieve). 

Let us know if you need further assistance on this.