Costain Secures £700M South Kensington Station Upgrade

LONDON, UNITED KINGDOM – Transport for London awarded a design-and-build contract valued at up to £700 million to British engineering group Costain on 22 September 2026 to deliver major structural upgrades at South Kensington Tube station. The contract runs from June 2026 to May 2028, with an option for a two-year extension through 2030. Enabling work begins in late 2026, leading toward a targeted scheme completion date in 2031.

What Does This Contract Cover?

The contract covers detailed design, enabling works, and heavy civil engineering to introduce full step-free accessibility across the Circle, District, and Piccadilly lines at South Kensington station. Costain will construct a new street-level accessible entrance at 34 Thurloe Street, reinstate an out-of-use eastbound platform for the District and Circle lines, and restore historic platform architecture. The engineering works interface directly with a parallel property scheme delivered by a joint venture between Native Land and Places for London, which will construct a four-storey commercial building known as the Bullnose along with 50 residential units designed by RSHP. Station civil works will be funded via TfL’s Business Plan alongside £12 million from the Royal Borough of Kensington and Chelsea and direct capital contributions from the 1851 Commission.

Key Contract Data

How Does This Compare to Similar Contracts?

Costain’s maximum framework allocation of £700 million matches the capital scale of TfL’s Bank Station Capacity Upgrade, which reached completion at £700 million in 2023 to expand passenger circulation by 45% (Source: Transport for London, 2023). Within the broader European transit construction sector, the South Kensington redevelopment relies on high-density transit-oriented commercial real estate to offset civil engineering expenses. Specific sub-contractor allocations for deep-level Piccadilly line lift shafts were not disclosed at time of publication.

Note: Independent verification of the final commercial split between TfL and Native Land for the Bullnose development was not available at time of publication.

Editor’s Analysis

The award to Costain establishes how mature metro systems are using multi-year framework contracts to bundle heavy sub-surface civil engineering with high-value air-rights property redevelopment. With the global urban rail sector accounting for 46% of passenger railway activity (Source: Fortune Business Insights, 2025), transit agencies increasingly depend on developer-backed equity partnerships to fund statutory accessibility mandates. Integrating commercial real estate risk directly alongside station capacity relief sets a critical operational template for future complex interchanges across Western Europe.

FAQ

Q: What specific accessibility upgrades will Costain construct at South Kensington?
A: Costain will install lift access connecting street level to the Circle, District, and deep-level Piccadilly line platforms via an entrance at 34 Thurloe Street. The works will also connect passengers directly to the pedestrian museum subway.

Q: What is the total financial value and duration of the contract awarded to Costain?
A: The contract carries a framework value of up to £700 million and runs from June 2026 to May 2028, with an optional two-year extension. Initial enabling works begin in late 2026, leading to full completion in 2031.

Q: Will London Underground train services be suspended during station reconstruction?
A: Transport for London has not announced full line closures, opting instead for phased works to maintain service on the Circle, District, and Piccadilly lines. A disused eastbound platform will be reinstated to ease platform crowding.