The combined incomes of the Moving Picture Company (MPC), Framestore CFC, The Mill, Barcud Derwen and The Farm in 2003 crashed through the £100m barrier taking 35% of the £290m taken by the top 50 last year.
Carlton-owned MPC was named as the highest earner, taking an estimated £30m plus, while The Farm received the producer vote for best post house.
The big five are also the largest employers with a combined staff of 880 people. The top 50 companies employ 2,800 people.
The survey results focused purely on independent companies (ie those not associated with a media owner, studio or production company) that complete work for TV.
The survey did not include post-facilities that earn money solely from film or commercials post-production. According to the UK Film Council, the combined value of the whole post-production sector last year was in the region of £1.4bn.