Road or highway 路 United Kingdom
How much did M25 motorway cost to build?
The M25 is the orbital motorway around Greater London, 117 miles long, built in stages over 11 years and officially opened by Prime Minister Margaret Thatcher on 29 October 1986 at a ceremony between junctions 22 and 23, when the final 13-mile section between Micklefield Green and South Mimms was finished. MoneyWeek and New Civil Engineer both give the total cost as GBP 909 million, GBP 7.5 million per mile, while Wikipedia says the total estimated cost of the motorway was around GBP 1 billion.
Final project cost
拢909 million
Approximately $1.33 billion
Cost basis: 1986
Highways AgencyCC BY 2.0
Cost evidence
Basis of the published figure
Final project cost1986
Project metrics
Key dimensions
- Total lengthMoneyWeek
- 188.3 km
Project record
Opened or launched
New Civil Engineer29 October 1986