Before May 2018, most of the trains serving Stevenage station were operated by Great Northern, lying on its Great Northern Route from London King's Cross to Peterborough and Cambridge. It was served by trains between Moorgate and Letchworth via Hertford North; these trains use Moorgate station in London. In May 2018 however, most Great Northern services were swapped with Thameslink services, and now the only Great Northern trains are two southbound departures per hour to Moorgate on Sundays only calling at all stations via Hertford North, and some weekday peak-hour trains between London King's Cross and .