A product offer is an additional sales opportunity that's displayed to customers before or after they complete checkout. This guide introduces pre-purchase product offers, and post-purchase product offers, and describes the available resources that you can use to build product offers in Shopify checkout. ## How it works You can build functionality in your app that enables merchants to provide the following experiences: - [Pre-purchase product offers](#pre-purchase-product-offers) - [Post-purchase product offers](#post-purchase-product-offers) ## Pre-purchase product offers > Shopify Plus: > [Checkout UI extensions](/docs/api/checkout-ui-extensions) that render on the information and shipping and payment steps in checkout are available only to stores on a [Shopify Plus](https://www.shopify.com/plus) plan. A pre-purchase product offer is an additional sales opportunity that's displayed to customers before they complete checkout. You can use a [checkout UI extension](/docs/api/checkout-ui-extensions) to build a pre-purchase product offer. The following example shows a pre-purchase product offer that renders at the [`purchase.checkout.block.render`](/docs/api/checkout-ui-extensions/latest/apis/extensiontargets) target: