Instructions:Click the link, fill in the details to get your voucher. It will enable you to buy their Xtra bite sandwiches for only £1 in-store @ Greggs the Baker, instead of the regular £1.70 they usually are.
"Voucher may be redeemed for any Xtrra bite for a £1 at participating Greggs shops, subject to availability. No cash alternative is available in whole or in part. Only one voucher per person may be redeemed. A unique identity number is clearly visible on each voucher."