Here is where you can find original information http://support.google.com/adwords/bin/answer.py?hl=en-GB&answer=1703648&topic=29171&ctx=topic Keep in mind Promotional codes are typically limited to one per customer. Promotional codes and coupons are intended only for new accounts and need to be used within 14 days of the account's creation. An expiry date usually applies, so keep in mind that you might have to use your promotional code within a limited period. If you're considering signing up with a service that offers you an AdWords promotional credit, make sure that you verify that the service has a relationship with Google. If you have any questions about an offer, please contact us before committing. If you receive a promotional code from a service that you have no business relationship with, be aware that the code might not be valid.