The high-street baker is running the 12-month trial with Moto, the motorway service provider. The initiative will be run as a franchise operation, which is new to Greggs.
The Greggs service station shop in Lymn, Cheshire, opens in December and will operate for a year before the company decides whether to roll out to a further 30 locations across the country.
Last month, Greggs announced plans to launch its first coffee shop, called Greggs Moment. The shop in Newcastle will sell a new range of bakery products, along with coffee and teas.
In September, Greggs commissioned its first digital ad campaign for a product launch.Follow John Reynolds on Twitter @johnreynolds10