diff --git a/src/wp-includes/js/wp-api.js b/src/wp-includes/js/wp-api.js
index d45219af72..a14d21fae6 100644
--- a/src/wp-includes/js/wp-api.js
+++ b/src/wp-includes/js/wp-api.js
@@ -1017,7 +1017,7 @@
 					success: function( newSchemaModel ) {
 
 						// Store a copy of the schema model in the session cache if available.
-						if ( ! _.isUndefined( sessionStorage ) && wpApiSettings.cacheSchema ) {
+						if ( ! _.isUndefined( sessionStorage ) && ( _.isUndefined( wpApiSettings.cacheSchema ) || wpApiSettings.cacheSchema ) ) {
 							try {
 								sessionStorage.setItem( 'wp-api-schema-model' + model.get( 'apiRoot' ) + model.get( 'versionString' ), JSON.stringify( newSchemaModel ) );
 							} catch ( error ) {