- If you change your rate plan in the middle of the month, you will be billed for the current plan plus the new plan (pro rata).
- The app fee is calculated by Shopify, so we cannot tell you the exact amount.
About App Installments, Upgrades, and Downgrades (Shopify Help Center)
When upgrading or downgrading a subscription on an app, the app will ask you to agree to a new app recurring billing amount, which Shopify authorizes because only one app recurring billing amount can be active per app at a time. The existing recurring app fee will be cancelled and replaced with the new fee.
The new flat billing amount for an app may be applied immediately or after the app's current billing cycle has ended. This varies from app to app.
If you upgrade from a lower rate to a higher rate plan in an app where the new billing amount is applied immediately, the fee will be split based on the price difference and the number of days remaining in the billing cycle. For example, if you start with a 30-day billing cycle on a US$5.00 plan and later upgrade to a 15-day billing cycle on a US$15.00 plan, you will be charged US$5.00 + (US$15.00 - US$5.00) * (15/30) = US$10.00 (15/30) = US$10.00 will be billed
If you downgrade from a higher rate to a lower rate plan for an app for which a new billing amount is immediately applicable, you will automatically be offered application credits based on the price difference and the number of days remaining in your billing cycle. These application credits can be used on future app purchases on Shopify.
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