Buses performance data

Measuring performance

We measure network performance by comparing the number of kilometres a route has done in the last quarter.

We compare each quarter to the same quarter of the previous year, rather than the last quarter of the same year. This is because factors affecting performance, like traffic conditions, can vary depending on the time of year, so this system makes it possible to identify underlying trends.

Scheduled kilometres may not be met because journeys are cancelled or suspended due to:

  • Traffic congestion
  • Staff availability
  • Engineering problems or mechanical breakdown

Quality of service indicators (QSI) are used to monitor service reliability.

Customer satisfaction

We ask a sample of passengers to give a score out of 100 on a wide range of bus service features, based on the journey they have just made. Passengers are carefully selected each quarter to represent all bus passengers in London.

Recent figures can be found in the latest quarter summary document below.

Defining the passenger journey

A passenger journey is defined as one ride on a single vehicle - not a bus trip from A to B as this may include more than one bus ride.

Statistics include all London Buses' contracted services but exclude any non-scheduled kilometres, London Service Permit routes and other special services.

Bus speeds reports

We monitor the speeds of buses to understand the impacts of changing road network conditions. Bus speeds include time spent stationary (for example at traffic lights and at bus stops). Bus speeds are available for the entire network, by borough, and by route.

  • All data is in miles per hour
  • All AM data is taken for Mondays to Fridays, School and Non School days, between 07:00 and 10:00
  • At Route level, some routes may be appear twice. This is because a service change happened during a period. A service change may include a change to a route structure, contract or operator

Factors affecting performance

Quarter 4 2019/20:   04 January 2020 to 31 March 2020

Operated mileage results were worse than Q4 a year ago, with an increase in some lost mileage categories and reductions in others. The Covid19 lockdown arrived towards the end of the quarter and was enough to significantly influence the results. Losses due to traffic delays decreased slightly to the lowest level seen for many years, driven initially by an ongoing reduction in roadworks and improved signal timings and boosted at the end of the quarter by a significant reduction in traffic levels caused by the lockdown. Conversely, the impact of the virus caused losses due to staff reasons, already above average due to bus operator recruitment issues, to increase further. Events causing significant delays to buses during the quarter included Brexit demonstrations in January, climate change demonstrations in February and various burst water mains and emergency works. Lost kilometres due to mechanical reasons were also higher compared with a year ago.

Until 2017/18, average bus speeds had been in consistent decline. The deterioration has been reversing over the past 2 years, although speeds remain much slower than in 2014. Overall bus speeds in Q4 were slightly higher than a year ago being boosted in the 2nd half of March by the Covid19 impact. Prior to the lockdown speeds had declined slightly compared with the same quarter a year ago in all areas except inner SW London.

Compared with Q4 a year ago, EWT has improved slightly with reduced disruption at the end of the quarter giving the results a boost. Prior to this EWT was slightly worse than a year ago though in general terms is still achieving some of the best ever results. Prior to the lockdown inner London was improved compared with last year whilst outer London recorded a deterioration. Punctuality of low frequency services was the same as a year ago whilst night buses departing on time deteriorated slightly.

International Bus Benchmarking Group

London is a member of the International Bus Benchmarking Group (IBBG), an international knowledge sharing network of bus companies. It was established in 2004 and is facilitated by Imperial College London.

Benchmarking is a continuous systematic process for evaluating the products, services, processes or organisations that are recognised as representing best practice for the purpose of organisational improvement. A blend of operational and customer metrics are used to track the performance of the bus network.

Every year, a review of buses performance monitoring is evaluated internally and presented to TfL's Independent Investment Programme Advisory Group (IIPAG) by Imperial College London to justify expenditure and ensure quality of service provided to passengers.