https://wpengine.com/support/cache/#Cache_Exclusions

Cache Exclusions

There are situations when a page should never be served from cache and the interaction should always be treated as unique, such as during checkout or login. Our servers will respect cache exclusion rules for pages, cookies and arguments.

Certain pages are excluded from server caching by default on all sites to help ensure functionality. Some of these default cache exclusions are:

• Legacy staging environment
• WP Admin area
• wp-login.php
• Pages named cart, checkout, or check-out
• Pages where a cookie containing wordpress_ has a value set

If we see WooCommerce on the site we add some extra default exclusions, so you don’t have to worry. We exclude the following pages for WooCommerce sites:

• /products-compare
• /coupon
• /my-account/lost-password
• /wp-json/wc
• /wc-api

As well as the arguments:

• add-to-cart=.+
• wp-api=.+

And finally, these cookies:

• woocommerce_items_in_cart=[1-9]+
• wp_woocommerce_session
• woocommerce_cart_hash

While we’d added some default exclusions there are still situations you may need custom cache exclusions put in place.

If you’re having issues with a form not submitting, or use a custom checkout URL, you may need to reach out to our support team to have that page excluded from server caching on your site.
At times a plugin or theme may not be carrying data correctly from page to page. If this happens there may need to be a cookie or arg excluded from caching.