Merchants on the Basic, Shopify, and Advanced plans can now use the theme editor to choose between the one-page checkout (default) or three-page checkout. Decide on what is best for your shop and your buyers, while knowing that your customizations and checkout settings will migrate seamlessly from one layout to the other. Plus merchants are unaffected by this change, and can still set their checkout layout in the checkout editor.
Learn more about how to change your checkout layout by visiting the help center.