Using promotional codes (coupons) in Google Adwords

Promotional codes (also known as coupons or vouchers) offer a credit to an advertiser's account. There's no way to ask for a promotional code, but Google and our partners will occasionally give out promotional codes as part of specific offers. Most offers require you to meet certain criteria before the credit will show up in your account, and they're typically for new advertisers with new accounts. You can enter the promotional code in the Billing tab of your account.