Sometimes having a discount code field on your checkout page can cause you to lose sales. A user that would have otherwise paid full price may see that field and go off on a search for “company x discount codes.”
This code recipe will hide the field from the checkout page and only display it if the code is passed through the URL in the format &discount_code=CODEID
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The Code Recipe
Adding the Recipe to Your Website
You can add this recipe to your site by creating a custom plugin or using the Code Snippets plugin available for free in the WordPress repository. Read this companion article for step-by-step directions on either method.