Accredited official statistics

Change of Heavy Goods Vehicle Classification in Road Traffic Estimates: user engagement

Published 20 May 2026

Applies to England, Scotland and Wales

Summary

The Department for Transport (DfT) publishes estimates of Heavy Goods Vehicle (HGV) traffic within the Road Traffic Statistics. We are seeking users’ views on a change to how HGV data is collected for Road Traffic Statistics. From 2028, roadside counts of HGVs will be simplified into two categories: rigid and articulated vehicles. This change will not affect the information available within the published summary statistics but will change the underlying data that is available to download via the road traffic geographic website and API.

This change will not affect the Road Freight Statistics, which are produced from a different data source.

Background

DfT collects vehicle count data to produce and publish Accredited Official Statistics on road traffic. DfT Roadside Surveys (manually enumerated counts) are conducted at approximately 7,000 locations each year and the department’s national network of around 300 automatic traffic counters (ATCs) provide continuous (24 hours a day, 365 days a year) counts. The HGV counts from these two sources are classified by type (rigid and articulated) and number of axles:

• Rigid HGVs: 2 axles

• Rigid HGVs: 3 axles

• Rigid HGVs: 4 or more axles

• Articulated HGVs: 3 or 4 axles

• Articulated HGVs: 5 axles

• Articulated HGVs: 6 or more axles

This six-category system is used in both DfT’s ATCs and roadside traffic counts.

These data are then used to produce the published Accredited Official Statistics on road traffic. The annual and provisional road traffic estimates publications contain total HGV traffic across all releases and tables, except for table TRA3105, which presents HGV traffic estimates for Great Britain split into the six-category system.

The individual count point data are separately published annually via the road traffic geographic website and API. The underlying data downloads include the HGV counts split into the six-category system.

Proposed changes

The proposed change is that HGV roadside counts will be classified by type only:

• Rigid HGVs

• Articulated HGVs

This two-category system will be used in DfT roadside counts from 2028 onwards. DfT’s automatic traffic counts will not change and will retain the six-category system.

This proposed change will enable the Accredited Official Statistics to continue in their current form in the statistical releases and tables published on GOV.UK. Table TRA3105 will continue to be produced by using a combination of the data from the roadside counts and ATCs.

DfT publishes the individual count point data via the road traffic geographic website and API. These data downloads will be affected by this proposed change. The data downloads will contain data using the two-category system, instead of the six-category system.

Reason for proposed change

The Code of Practice for Statistics emphasises that government statisticians should consider adjusting outputs where appropriate, to maintain public value. In assessing against the dimensions of quality and value, we believe that the proposed change would enhance user value by improving the quality of the statistics due to minimising the risk of reducing sample sizes.

Roadside traffic count enumerators have reported difficulty accurately counting axles during busy periods, whilst the current level of granularity makes it more challenging to adopt emerging technologies. Reducing the number of classifications would allow enumerators to focus on a smaller set of vehicle types, potentially leading to improvements in data quality and supporting the modernisation of counts,

How to feed back

We are inviting users of road traffic statistics to provide comments on the proposed change by Monday 31 August 2026.

We will take feedback in all formats, but it would be helpful to use the template and questions provided. Please submit the following completed template to roadtraff.stats@dft.gov.uk

Response Template

Question	Response guidance
1) What type of organisation do you represent?	Arm’s length body or public agency; Local or combined authority; Devolved administration; Transport operator or infrastructure body; Industry body or consultancy; Academic or research organisation; Media or communications organisation; Charity or third sector organisation; Member of the public; Other (please specify)
2) How do you currently use HGV traffic statistics?	Research; Planning and infrastructure; Policy development; Commercial decision-making; Personal interest; Other (please specify)
3) Do you currently use count-point level data split by axle from our website? Note: the individual count point data available via the road traffic geographic website and API will be affected by this proposed change. The data downloads will contain data using the two-category system, instead of the six-category system.	Yes; No; If yes, please explain and provide an example of the impact this change will have.
4) Would it be beneficial to you if we continued to publish national level breakdown of HGVs using the original 6 axle-based categories? Note: Official Statistics on HGV traffic estimates for Great Britain split into the six-category system will continue to be produced by using a combination of the data from the roadside counts and ATCs.	Yes; No; If yes, please tell us why.
5) What level of geographical detail do you typically use?	National; Regional; Local authority; Road‑level; Other (please specify)
6) Any other comments or suggestions?

Subject to the views of users, we intend to implement this change in 2028, with the first publication of the data in Spring/Summer 2029.