Go to System → Settings → General

Enable/Disable new review entry. This will change visibility or completely hide the write review form on the StoreFront product page.

Four options available:

• Do not allow - the write review form will be hidden for any customer or visitor

• Any customer or visitor - anyone allowed to post new product's reviews

• Registered Customer - only logged-in customers allowed to post product reviews

• Customer with verified order - only logged-in customers who purchase the product allowed to post purchased product's reviews