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Is it possible to use the Self portal for those customers who don't have the Contract Terms activated on their subscription?

Summary

In Chargebee, you will be able to create a subscription in contract only for the new customers. For an existing customer, you can create a new subscription and cancel the previous subscription.

To do this via API, use

1. Cancel the Subscriptions at the end of the renewal: Use the Cancel Subscription with end_of_term = true

2. Re-create the subscription with the Contract Billing fields Create a Subscription with the contract attributes. 

You can allow your existing customers to manage their current subscription via a self-serve portal.

Note:
1.The Contract Terms feature is currently supported only in the In-app Checkout via API.
2.Contract terms once applied to a subscription, can not be removed from the subscription.
3.You can not pause a subscription that is created on contract terms.

To know more about Contract terms, click here.

Related articles and Documentation

Is it possible to have a single plan with different options for contract length?(such as 3 months, 6 months or forever).