How to Make PayPal Discount Codes

Non-hosted Add to Cart Button
1. Ensure you are not using using a hosted 'Add to Cart' button. In order to use a discount code, you must have a non-hosted button. To create one of these through PayPal, log into your PayPal account and click the 'Merchant Services' tab.
2. Select 'Merchant Tools.' In the 'Website Payment Standard' section, choose the button you want to make.
3. Click 'Create your button now' and fill out all fields. Then go to 'Step 2: Track inventory' and uncheck the 'Save button at PayPal' box.
4. Click 'Create Button' and follow the 'Remove code protection' link. At this point you will be able to see the unencrypted HTML code of the new button. Merely click 'Select Code' and copy it to your website.
Using JavaScript
5. Use JavaScript to add a discount code field to your check out now that you have a clear text button. You can do this through PayPal premier or business accounts.
6. Write the custom JavaScript (numerous examples of which can be seen on Paypal's X Developer Network) on the website you are trying to add the button to.
7. Ensure the script is capable of retrieving the discount code from the buyer, and then passing the new amount on to PayPal for payment.