It is 9 miles 28 chains (15.0 km) down the line from St Pancras and is situated between Hendon to the south and Elstree & Borehamwood to the north.

The station was built by the Midland Railway as simply "Mill Hill" in 1868 on its extension to St. Pancras, being renamed in 1950.

Prior to the major engineering works to create the "Thameslink Box" at St Pancras, Mill Hill Broadway was also served at peak times by Moorgate fast trains.

In 2009, several morning peak southbound fast services (stopping only at West Hampstead Thameslink) and several evening peak northbound fast services (stopping only at West Hampstead Thameslink) were reinstated.

From March 2009, Southeastern and Thameslink began running some peak hour trains from Sevenoaks to Luton,[4] though in the off-peak these services turn back at Kentish Town.