Trip generation

Trip generation estimates the amount and type of new trips at new developments in London. Find out about our preferred trip generation method.

Method

Surveys

One of the best ways to assess current and future trip generation is to survey current movements at the same site or somewhere similar. You can use information on how people travel now to predict how people will travel in future.

If possible, you should also survey all the current delivery and servicing movements to and from the site.

See survey instructions and use our data collection template:

TRICS

You can use the TRICS database which includes the results of travel surveys from many developments across London and the UK. The sites used should be similar to the proposed development in terms of location, scale, land use and car parking.

Mode share

Once you've estimated the total number of new trips at your new development, split them by transport mode using similar site surveys. Where surveys are not possible, the borough level mode share data available in our strategic modelling dashboard can be used. This helps us understand how London's walking, cycling, public transport and highway networks may be affected.

Similar site surveys or borough level data may not accurately reflect the characteristics of your development and you may think that adjustments are required. Please explain and justify any adjustments you make clearly in your Transport Assessment (TA).

Cumulative impacts

You can combine trip generation for a new development with trips generated by nearby developments for your Transport Assessment (TA). This helps us assess cumulative impacts on the London-wide network.

Growth assumptions and infrastructure investment

Your TA should assess how travel and transport will be at your new development when it's occupied (not now). So, you may need to use growth assumptions about how travel and freight in London, or the local area of your planning application, will change in future.

Alignment with London's statutory spatial development strategy (the London Plan) ensures a robust and consistent approach that reflects London's unique characteristics. Borough level growth projections from core TfL forecasts are available from our strategic modelling dashboard. This data must only be used to inform assumptions, at a borough level, relating to future changes in travel demand volume, mode share and distribution in London. Please contact strategicmodelling@tfl.gov.uk for access to London specific data.

Infrastructure investment will also play a role in how trips generated by a new development impact London's walking, cycling, public transport and highway networks. So, you need to include information on future infrastructure investment in your planning application.

We do not support the use of TEMPro (NTEM) derived growth factors to inform projects in London and recommend that London specific forecasts are used instead. The London specific forecasts are aligned with the London Plan, for example, in terms of growth (population and employment) and policy relating to the provision of car parking.

Trips generated by construction

You can use our tool to estimate trips generated by construction:

Use a different method

If you want to use another method for trip generation, or other data sources and decisions for mode share, your assessment approach should be approved by us through our pre-application services. You must explain and justify it in your Transport Assessment.