Mr Milburn has been an MP since 1992
The former cabinet minister Alan Milburn is to stand down as an MP at the next election.
Mr Milburn, the former health minister, told his local party in Darlington of his decision on Saturday morning.
He said: "Standing down as an MP will give me the chance to balance my work and my family life with the time to pursue challenges other than politics."
He left frontline politics in 2003 and said he had never wished to return nor had he regretted the decision.
A spokesman for Gordon Brown said Mr Milburn had told the prime minister of his decision during a telephone call on Saturday morning.
He said: "Gordon thanked Alan for his many years' service to the country and the Labour Party, and wished him well for the future."
Mr Milburn did not get caught up in the MPs' expenses scandal despite claiming more than £20,000 in second home allowance in each of the years between 2004 and 2008.
MP for Darlington since 1992, Mr Milburn was health secretary between 1999 and 2003, when he resigned citing lack of balance between home and work.
He currently has an advisory role, chairing a commission on social mobility for Gordon Brown.
Mr Brown's spokesman said the report on access to professions which Mr Milburn was commissioned to write would be published soon.
Mr Milburn is expected to be one of the highest earners in the Labour Party when figures for his work outside parliament are made public from 1 July under the new Commons reforms rules.
He currently works for firms including Lloyds Pharmacy and PepsiCo.
Tory MP David Maclean has also announced he is to stand down at the next General Election, due to ill-health.