Set Up Usage-Based Pricing


This pricing model is Alpha and still in development. If you want to implement this pricing model then please submit a request.

Usage-based pricing lets you charge users on a recurring, monthly basis for their usage in your app – e.g., a user sends 100 SMS marketing messages in a month.

You can choose to charge a flat monthly base fee as well as a per item charge with this model.

At the end of the billing cycle, Wix makes an SPI call to request the usage-based charges, and charges the user accordingly.

You define a usage cap with the Get Charge Limit endpoint that Wix calls when a user chooses to upgrade the app plan. This can be increased later on by the user, once they’ve purchased a plan.

Wix doesn't notify users when a usage cap hits the limit – it's your app's responsibility to let them know.

Read more about implementing the SPIs of custom charges.

Add a usage-based pricing plan

  1. Go to the Wix Developers Center > Pricing > Pricing Plans
  2. Select either the Freemium or Premium business model.
  3. Click Add Plan
  4. Select Usage-based, and fill in the plan details.
  5. There are two options for a usage-based plan:
    • With base fee: The amount that the user will be billed for during the initial checkout, and then recurring at the beginning of each billing cycle.
    • Custom: No base fee or charge at checkout and the app has only usage-based charges which are applied at the end of each billing cycle.
  6. Additional charges: Add a short description of the way the additional charges are being made or calculated. Description examples:
    • $0.50 per SMS message sent.
    • 0.75% of additional revenue generated by the app.
    • $0.05 per extra order above initial 500 orders.
    • 1.0% transaction fee.
    • Additional charges may apply.

If you add a price please add it in the {}, e.g., if you charge based on the usage of SMS, please > add it like this: “{0.5} per SMS”, in the app listing it will look like this: “0.5$ per SMS”. This > ensures that the amount is automatically converted to other currencies.

*The default currency is in US$


  1. Add the Custom Charges SPI component in the Extensions tab of the Wix Developers Center. This lets you:
    • Add your app's charges to the invoice that Wix sends to site owners.
    • Receive notifications about charges that Wix doesn't accept, created invoices, or when customers increase their charge limit.
    • Keep your customers informed about how much your app would charge them if Wix were to send an invoice at this time.
  2. Listen to the Paid Plan Changed webhook to identify when users change their plan in the middle of a billing cycle – this is relevant for apps with more than one pricing plan where users can upgrade to a higher plan.
  3. The Wix pricing page isn’t available for usage-based plans. Therefore your pricing page will need to be external and you’ll need to implement the Get URL API call.

How it works

  1. A user chooses to upgrade to one of your usage-based plans. Wix calls the Get Charge Limit endpoint to retrieve the initial charge limit for a paid instance of your app. This happens every time a customer is upgrading to a paid version of your app.

  2. User accepts the terms and checks out, if there is a base fee, the user will be billed for it during the checkout.

  3. The user is able to increase the charge limit amount at any time. If the user increases the limit the Charge Limit Updated endpoint is triggered. A user can do this in their Premium Subscriptions > More Options > Manage Charge Limit.

  4. The user is able to see the sent amount at any time. Wix will call the List Charges endpoint to receive the charges for that particular time.

  5. At the end of the billing cycle, Wix will ask for the usage-based charges using the List Charges SPI, and make sure that the charges are within the limit. If not, Wix will call Charges Rejected Event.

  6. After a successful charge, Wix will call the Invoice Created endpoint.

Important things to know about usage-based pricing

  1. As this is still in development, we don’t currently support the Wix Pricing Page or downgrades.

  2. Mixed billing models are not supported right now. You won’t be able to add a recurring plan and an additional usage-based plan.

  3. If the user upgrades to another plan in the middle of the billing cycle, the usage-based charges should be handled on your end and added as a line item. You should listen to the Paid Plan Changed webhook to see when users change their plan in the middle of a billing cycle. Wix will ask for the charges at the end of the cycle of the new plan. Example:

Was this helpful?