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By the end of July, your customers will no longer be directed to checkout.shopify.com to complete their purchase. Instead, their entire shopping experience—from homepage to checkout—will take place on your domain. No more domain switching.
Seeing your branded domain at checkout, coupled with the free SSL certificate we provide all merchants, will give your customers the confidence they need to tap that buy button again and again.
Checkout on your own domain is free for all merchants and will be activated automatically—no setup required. The checkout is one of the most important parts of your store, and now it belongs to you.
What if I don’t have a custom domain?
While a custom domain is a strong signal that you’re an established business, you don’t need one to get some of the benefits of having your checkout on a custom, branded domain.
All Shopify stores get a store-name.myshopify.com domain free of charge, and your checkout will now live there. Your customers will still see your store name in the URL, but it will appear alongside the trusted Shopify name.
If you’d like to take advantage of a fully branded experience, you can easily purchase a domain right in Shopify.
What if I'm on Shopify Plus?
Starting today, all those that use Shopify Plus can get a free Extended Verification (EV) SSL certificate. These EV certificates add another level of trust to merchant’s store by clearly showing customers who they are and that their personal information is protected.
As well, because Shopify Plus allows for the customization of the checkout’s liquid code, the migrations will happen on August 20th, giving Shopify Plus merchants extra time to make any necessary changes.
Can I edit the look of my checkout?
Your checkout is already rigorously tested, secure, and optimized for sales by ecommerce experts in order to give you and your customers the best purchase experience on the internet. This data-driven team is constantly looking for new ways to improve your checkout, so you never have to.
Because advanced customizations usually require dedicated teams to manage, editing the look and code of your checkout and using Shopify Scripts are a Shopify Plus-only feature.Source: Shopify Blog