[6] The line was then leased by the Great Northern Railway[7] in 1850 and subsequently purchased in 1898[8] and through services run from London King's Cross to Cambridge.

The extension of electrification through to Cambridge was completed in 1988[9] under Network SouthEast and the track improved to increase speed.

Occasional services are run by 12-car trains [10] allowing them to stop only at Royston & Letchworth Garden City where the platform is long enough to accommodate them.

The Down platforms at Shepreth and Foxton were extended in 2017 to allow 8-car trains to stop without blocking the level crossings.

An alternative route via the West Anglia Main Line links Liverpool Street to Cambridge now provides mainly stopping services though some peak hour trains stop only at Tottenham Hale and Audley End.