Cumbrian-based rail engineering contractor WA Developments, number 42 on the list, and London maintenance firm Bridgen Enterprises, number 58, both benefited from the increased demand in the rail sector.
Turnover at WA Developments has increased from £3.1m in 1999 to £21m in 2002. In October it bought cult haulage firm Eddie Stobart.
Oxfordshire-based ServiRail, 50th on the list, saw its sales rise from £2.5m to £16m between 1999 and 2002 thanks largely to its work on preparing St Pancras Station for the channel tunnel link.
Of the non-railway contractors on the list, the fastest growing is facilities manager Coflex, at number 33. It will run the Swiss Re tower when it opens next year. At number 46 is building services contractor Paul Earl.