Amazon is making one of the biggest advantages of its Prime membership available beyond Amazon.com. Merchants using Amazon’s Multichannel Fulfillment service in the U.S. can now offer fast, free Prime delivery directly on their own websites, without paying an additional fee specifically for the Prime delivery option.

The move gives independent brands a way to put the familiar Prime badge next to products sold through their own storefronts while continuing to use Amazon’s fulfillment network behind the scenes. Amazon says the feature is available now to new and existing Multichannel Fulfillment (MCF) merchants, which already number in the hundreds of thousands in the U.S.

The important distinction is that this does not mean merchants suddenly get Prime shipping for free. They still pay Amazon’s standard MCF fulfillment fees. What Amazon is removing is an additional cost for adding Prime delivery as a shipping option.

For shoppers, the experience is designed to be relatively straightforward. A Prime badge can appear on eligible product pages, and customers can select Prime delivery during checkout. After the order is placed, Amazon verifies the shopper’s Prime membership and fulfills the order using the merchant’s inventory stored within Amazon’s logistics network. The merchant still handles the customer-facing order confirmation and tracking experience.

There is also a small but notable change to how Prime authentication works. Shoppers do not need to sign in to Amazon during checkout to use the Prime delivery option. Instead, Amazon verifies Prime membership after the order has been placed.

That could make the feature considerably less disruptive for merchants that have invested in their own checkout systems. Amazon says merchants do not need to change their payment processing, order management systems, or store policies to enable the new shipping option. The company also says setup is 70% faster on average than enabling standalone Buy with Prime.

For Shopify merchants, Prime delivery can currently be enabled through Amazon’s MCF and Buy with Prime app. Amazon also plans integrations through its Selling Partner API, with fulfillment technology partners including Fulfil, LingXing, and WebBee expected to support the option.

Amazon says the early response has been strong. More than 40% of eligible orders among early merchant adopters have shipped with Prime delivery on average. One merchant cited by Amazon, Skinnies Instant Lifts, reported a nearly 10% increase in sales after adding Prime delivery, along with orders shipping in about a day and a half and a sharp reduction in “where is my order?” inquiries. Those results are individual merchant results rather than a guarantee of what other businesses will see, but they illustrate why Amazon thinks its delivery brand can matter even when the shopper is not buying from Amazon itself.

Amazon is also pairing the Prime delivery announcement with a separate incentive for merchants that use its fulfillment infrastructure. The new MCF Preferred Pricing Program can reduce fulfillment fees by 15% to 25% during the first six months by combining discounted MCF fulfillment fees with Fulfillment by Amazon credits on units shipped.

The program is available without a contract or long-term commitment, and Amazon says merchants can enroll through Seller Central with one click. The discounts automatically apply when eligible orders are shipped.

That second piece is arguably just as important as the Prime badge. Amazon is increasingly positioning its logistics network as infrastructure that merchants can use regardless of where the actual sale happens.

Multichannel Fulfillment already allows merchants to use Amazon to store, pick, pack and ship orders placed through their own websites, social media channels and other online retailers. Amazon says MCF operates across 11 countries, while merchants using both MCF and Fulfillment by Amazon can share inventory across their sales channels. According to Amazon, U.S. merchants using the two services together have reduced out-of-stock rates by an average of 19% and improved inventory turnover by an average of 12%.

This also puts the new Prime delivery option in an interesting position alongside Buy with Prime. Buy with Prime already allows independent merchants to offer Prime shopping benefits on their own websites, with Amazon handling fulfillment as well as parts of the post-purchase experience, including customer service and returns.

The new MCF option is more narrowly focused on delivery. Merchants can keep their existing checkout, payments, order management, customer service and returns processes while using Amazon’s logistics network to provide Prime delivery. In other words, Amazon is making its fulfillment infrastructure easier to plug into a merchant’s existing business rather than asking the merchant to hand over the entire shopping experience.

That distinction could matter to brands that have deliberately built their own direct-to-consumer storefronts. They can maintain the relationship with customers and the branding of their own websites while borrowing one of Amazon’s most recognizable promises: fast, free Prime delivery.

It is another sign that Amazon wants to sell more than products through its marketplace. The company is increasingly selling the infrastructure behind the marketplace, from fulfillment and shipping to inventory management. If merchants can use that infrastructure while continuing to own their storefront and customer experience, Amazon gets another way to extend its logistics network into parts of e-commerce that do not happen on Amazon.com.

For shoppers, meanwhile, the Prime badge may start appearing in more places than expected. Prime is no longer necessarily a signal that you’re shopping on Amazon. Increasingly, it can simply mean that Amazon is somewhere behind the delivery.