A signalling system fault on August 12, 2026, between London Paddington and Heathrow Airport / Reading caused some lines to close, disrupting train services along this route.
Impact on Elizabeth Line and GWR Services
The fault affected Elizabeth line and Great Western Railway (GWR) trains, resulting in cancellations, delays up to 20 minutes, and adjustments to timetables. Operators revised schedules to manage lower service availability, with fewer trains running between the affected stations.
Affected Routes and Stations
Train disruptions impacted key stations between London Paddington and Reading including Slough and Maidenhead. Services on Heathrow Express and Elizabeth line trains operating between London and Heathrow Terminal 5 also faced delays and operational
restrictions.
Official Statements and Timelines
National Rail confirmed the fault caused line closures and operational changes. A statement noted: “A fault with the signalling system between London Paddington and Heathrow Airport / Reading means that some lines are closed.” Initially, disruptions were expected to last until 14:00 with reduced speed services running. Later, National Rail extended the expected disruption time until 19:00, also warning that cancellations or delays up to 20 minutes remained likely.
“As a result, fewer trains than normal are able to run between these stations and may be cancelled, delayed by up to 20 minutes or revised. Disruption is expected until
19:00,” National Rail added.
Passenger Delays and Service Reductions
Following the signalling fault, trains operating between London Paddington and Reading slowed to reduced speeds. Passenger journeys were subject to cancellations and delays of as much as 20 minutes during the extended disruption period on August 12, 2026.
The prolonged disruption primarily affected commuter and regional services on the busy London corridor including connections on the Elizabeth line to Heathrow and Reading.
