Crossrail (Elizabeth Line): The 4-Year Delay
Crossrail was due to open in December 2018 at a cost of 14.8bn GBP. It opened in May 2022. In July 2021 the NAO put the forecast cost at 18.9bn GBP, a 28% nominal increase on the 2010 budget, within an 18.8bn GBP funding package. The NAO published two scathing reviews (2019 and 2022) identifying signalling and systems integration as the central failure.
18.9B GBP
forecast cost (NAO, July 2021)
3.5 years
behind schedule
+28%
nominal increase on the 2010 budget (NAO)
What went wrong, per the NAO
The 2019 NAO report identified three structural failures:
- Signalling integration was scheduled in parallel with civil works finalisation. The three signalling systems (Network Rail mainline, Crossrail central tunnel, and Heathrow approach) had to be integrated by 2018. They could not be, because the central tunnel civils were not complete in time.
- The single-systems-integrator model was abandoned mid-project. Crossrail Ltd took on the role itself, without the capability to do so. The 2022 NAO report singled this out as the "most significant strategic error".
- Cost-to-complete forecasting was missing for the systems work. Civils were tracked in detail, but systems integration cost had no equivalent earned-value baseline. Slippage was invisible to the board until it had compounded into a year-long delay.
Sources
- UK NAO (May 2019). Completing Crossrail.
- UK NAO (July 2021). Crossrail: a progress update, key facts: £18.9bn forecast cost, 28% nominal increase from the 2010 budget of £14.8bn. Read 8 October 2026.
- UK NAO. Lessons learned from major programmes.