Programme Status Breakdown
Delay Distribution (Weeks)
Announced vs. Current Cost — All Schemes (£m)
Cost Escalation Forecast to 2032 — Active Schemes
Crossrail — 4 Years Late, £4.1bn Over Budget
Opened 24 May 2022, nearly four years after the December 2018 target. Total cost reached £18.9bn against a £14.8bn baseline — a £4.1bn overrun. Repeated signalling failures, contract disputes and COVID-19 disruption combined to produce one of Europe's most-scrutinised infrastructure delays. Full end-to-end services did not commence until May 2023.
HS2 Euston — At Least 9 Years Late, £3.4bn Over
Originally due to open to Euston in 2026. No revised date has been set for the Euston terminus. The PAC warned costs could approach £80bn for Phase 1. The station was scaled back to six platforms with private finance — a route the Public Accounts Committee expressed scepticism will materialise. Tunnel boring continues but station construction has not started.
Hammersmith Bridge — 525% Cost Explosion
Closed to motor traffic in April 2019. Initial repair estimate: £40m. Current estimate: £250m — a 525% increase. Funding disputes between LBHF, DfT and TfL remain unresolved as of 2026. The bridge risks remaining closed to vehicles until 2035, making it nearly two decades from closure to possible reopening — for a Victorian structure in one of London's most affluent boroughs.
Four Lines Modernisation — 7 Years Behind, £1.3bn Over
The 4LM digital signalling upgrade for Circle, District, Hammersmith & City and Metropolitan lines was originally due to complete around 2022. The programme budget rose to £5.541bn (from £4.2bn) by June 2024, with TfL's own Q2 2024/25 report noting the estimated final cost already exceeds even this figure. Several signalling areas remain unstarted as of 2026; realistic full completion is late 2020s.
New Hospitals Programme — £56bn Nationally
Boris Johnson's 2020 pledge of "40 new hospitals by 2030" has become a £56bn programme extending to 2045–46 — a £33.8bn increase on 2023 estimates. London schemes include Whipps Cross, Charing Cross, Hammersmith Hospital, St Mary's Paddington and Sutton SECH. Seven RAAC-risk hospitals will miss the 2030 deadline, now expected to open 2032–33.
Piccadilly Line — New Trains Entering Service Jun 2026
94 new Siemens Inspiro trains were ordered in 2019. Following years of delay, new trains completed first passenger rides in June 2026 — a significant milestone. Full fleet rollout continues through December 2026 to June 2027 (TfL programme). TfL confirmed an additional £409m for depot upgrades in February 2026, raising the total programme to £3.4bn from £2.994bn. The trains are the first new deep-tube stock in three decades.
| Scheme | Status | Announced | Current Est. | Variance | Delay | ETI | Stranded | Detail |
|---|
Methodology & Sources
CPD Index (0–100): CPD-C (Cost Performance) measures the proportion of schemes delivered at or near announced cost, with a severity penalty for overruns greater than 25%. CPD-D (Delivery Performance) measures the proportion of schemes free from significant delay, with a minor penalty for smaller slippages. The combined CPD score is the unweighted average. A score of 100 indicates a perfect delivery record; 0 indicates complete systemic failure.
Clock: The live clock shows the cumulative active cost overrun on schemes with confirmed cost increases that are currently active (not paused, cancelled, or completed), compounding at a blended BCIS inflation rate of 3.8% per annum from base epoch 30 April 2026 BST. Active overrun base: £14.621bn (Piccadilly £406m + NHP London £3,500m + DLR Thamesmead £820m + 4LM £1,341m + HS2 Old Oak Common £570m + HS2 Euston £3,400m + Lower Thames Crossing £4,374m [updated Jun 2026] + Hammersmith Bridge £210m). Paused and cancelled schemes (Bakerloo Line Extension, Crossrail 2, Rotherhithe Bridge) and completed schemes are excluded from the clock.
Cost data: Announced costs are taken from original TfL Business Plans, GLA Budget papers, DfT/HS2 Ltd announcements and parliamentary statements. Current estimated costs are drawn from TfL Annual Reports, NAO reports, London Assembly Transport Committee papers, GLA Budget scrutiny documents, Mayor of London press releases, BBC London, and the Evening Standard.
Delay data: Weeks of delay calculated from original target completion date versus revised target or current date where no revised target exists. Where no completion date was formally set, delay is shown as — (not quantifiable).
2032 projection: BASE_OVERRUN × 1.038⁶ = £14,621,000,000 × 1.2504 ≈ £18,287,788,827. This represents the inflation-adjusted value of today's confirmed active overruns by the end of the current Mayoral term in 2028 and projected to 2032.
Primary sources: TfL Annual Reports & Business Plans · GLA Budget & London Assembly · National Audit Office · BBC London · GLA Capital Funding & Delivery Report Dec 2025 · NAO HS2 Update July 2024
Disclaimer: This tracker is an independent professional assessment prepared by QuintinQS. It is not affiliated with TfL, the GLA, the Mayor of London, or any government department. All figures are drawn from publicly available sources and are correct as of the date shown. Cost projections are indicative only. Part of the British Isles CPD series.
CPD Index — cost cap: The cost overrun % contribution to CPD-C is capped at 50 points — schemes with overruns above 100% score the maximum on this component. This prevents extreme outliers (e.g. schemes with 200%+ overruns) from distorting the index beyond its intended range.
CPD — about this acronym: CPD stands for Continued Prolonged Delays — a deliberate reference to Northern Ireland's Central Procurement Directorate, rebranded as Construction, Procurement, Delivery — the NI Executive body whose mandate is to ensure public infrastructure is built on time and on budget. The name is intentional.