WooCommerce URL Coupons v2.13.1

Extend or Automate your Coupons with WooCommerce URL Coupons
The URL Coupons extension allows you to add a unique URL to any coupon in your WooCommerce store. When this URL is used or clicked on, it automatically applies the coupon discount and can (optionally) add products to the customer’s shopping cart.
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URL coupons gives you the perfect way to make your print advertising actionable, or you can also help customers remember coupons so that they actually complete purchases. Measure the success of your pay-per-click ad campaigns by using a coupon URL, or use the plugin to only allow URL coupons.

Increase Conversions by Removing Coupon Fields
Studies from major analytics companies like KISSmetrics have shown that coupon boxes are conversion killers. Customers leave your site to search for coupons, and may not return. URL coupons gives you the flexibility to be your only coupon method.

You can allow the plugin to hide your coupon code fields in the cart and/or checkout so that only URL coupons can be used. This way, customers with coupons automatically have them applied by visiting your URL, while other customers never leave to go coupon hunting.