Overview

A Storefront may be configured in a "checkout only" configuration, where only the checkout portion of functional. This configuration would be used when you already have a front-end storefront in place and only need to add the checkout to this fronte-end site.

Steps

Here are the steps for using a StoreFront as a Checkout Only theme.  Placing a theme into Checkout Only mode causes the theme to generate a slimmed down version of header/footer navigation and redirect any other traffic to the StoreFront to your main website.  Using a StoreFront in a Checkout Only mode is the fastest way to add a responsive checkout experience to an existing website.

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At this point the StoreFront is in Checkout Only mode.  If  

Legacy Checkout Migration with SSL certificates

If you have an existing legacy UltraCart checkout you can continue reading Using existing SSL certificate for a checkout only theme.