Understanding the “true cost” of transport is central to achieving a more sustainable, inclusive and efficient transport system. While traditional appraisal methods capture many economic impacts, recent discussions across the sector highlight growing concern that significant social, environmental and behavioural dimensions remain underrepresented.

Beyond economic cost: recognising social impact

Transport appraisal has historically focused on economic efficiency: travel time savings, congestion, collisions and infrastructure costs. However, interviewees emphasised that this approach risks overlooking how transport costs and benefits are distributed across society.

As highlighted by Dr Faheem Ahmed Malik, FHEA MCIHT FMAIEME PhD, Lecturer in Transportation at Edinburgh Napier University, current methodologies tend to treat individuals as broadly equal in how they experience costs. In practice, this is not the case. For higher-income users, an additional travel cost or time delay may have limited impact. For lower-income individuals, however, the same cost can represent a significant burden - potentially restricting access to employment, healthcare and education (CIHT, 2024a)

Transport therefore plays a critical enabling role in everyday life. When access is constrained, whether by cost, time or availability, the effects extend well beyond mobility, influencing wider social and economic opportunity.

Transport costs are also shaped by intersectionality - the way gender, ethnicity, age, socio-economic circumstances and location combine to influence how people experience mobility. Recent research on cycling safety and e-cargo bike use shows that travel behaviour and transport risk are not experienced uniformly. In one study, rider safety under variable environmental conditions was found to differ according to factors including age, gender, infrastructure type and weather conditions, reinforcing the need to understand transport outcomes at a far more granular level. In another, the attractiveness of e-cargo bikes for small businesses was shown to vary with journey distance, rainfall, temperature and time of day, illustrating how context and user characteristics interact to shape mode choice. Together, these findings underline a wider point for transport appraisal: average costs and average users are poor proxies for lived experience (Malik and Dala, 2022; Malik et al., 2023).

The key implication is clear:

• A single “average” cost metric cannot adequately capture the lived experience of different groups.
• Social equity and user behaviour needs to be explicitly embedded within how the true cost of transport is assessed.
  

Externalities and the limits of current pricing approaches

The idea of externalities - costs imposed on society but not directly borne by users - remains central to debates on transport pricing.

Rod Macdonald OBE FICE MInstRE, Visiting Professor of Holistic Civil Engineering at Heriot Watt University highlighted how many impacts of transport are still only partially reflected in pricing systems. These include: 

• Health impacts from air pollution
• Road safety outcomes
• Infrastructure damage from heavy vehicles
• Wider societal costs from inactivity or isolation

Dynamic pricing and telematics-based systems offer opportunities to better align charges with impact. For example, road use could be priced differently depending on real-time congestion levels, location or vehicle type, rather than relying on blunt national charges. However, the introduction of such systems raises practical and political challenges, particularly around privacy, public acceptability and perceptions of fairness (CIHT, 2024b).

The challenge of decarbonisation: green vs sustainable transport

A recurring theme across both interviews is the distinction between environmentally “green” transport and genuinely “sustainable” transport.
Electrification of vehicles provides clear carbon benefits. However, interviewees emphasised that this alone does not resolve wider issues such as:

• Congestion
• Accessibility for people with different needs
• Inequalities in access to transport options

As Dr Faheem Ahmed Malik highlighted that pursuing purely environmental objectives risks neglecting the social dimension of transport systems - for example, the needs of disabled users or those unable to rely on active travel modes, the value of personal interaction and access to community events or places.
Sustainability therefore requires a more balanced approach, integrating:

• Environmental outcomes (emissions reduction)
• Social inclusion (accessibility and equity) 
• Economic efficiency (value for money and productivity)
  

Decarbonisation is therefore not just an engineering challenge - it is also a collective action problem. Behavioural theories such as Social Dilemma Theory suggest that people are more likely to support action for a shared good, such as a stable climate, when they believe costs and benefits are being distributed fairly. Where policies impose visible short-term costs - for example through road user charging, restricted access zones or the need to purchase expensive new vehicles - while benefits appear longer-term or diffuse, resistance should not simply be dismissed as irrational. It is often a predictable response to perceived unfairness. This is especially important where lower-income households, disabled users or rural communities face extra burdens without realistic alternatives.

This principle has deep roots in international environmental thinking. At the 1972 Stockholm Conference, Indira Gandhi argued that environmental improvement could not be separated from the realities of poverty, warning that “the environment cannot be improved in conditions of poverty. Nor can poverty be eradicated without the use of science and technology.” Her point remains highly relevant to transport policy: climate action will not succeed if it adds further pressure to those already facing economic hardship or social exclusion. A similar logic underpins the Kyoto Protocol’s principle of common but differentiated responsibilities, which recognises that those most responsible for emissions should take the lead in addressing them. Applied within countries, this suggests that those who have benefited most from high-carbon mobility may also have a greater capacity - and responsibility - to bear the costs of transition than those with the fewest alternatives (Gandhi, 1972; UNFCCC, n.d.).

For transport policy, the implication is clear. A sustainable system cannot be delivered through technology mandates or pricing mechanisms alone. It requires visible mutual benefit - cleaner air, safer streets, better access to work and healthcare, affordable alternatives, and improvements people can see in their daily lives. Without that social contract, efforts to decarbonise transport may stall, trigger backlash, or deepen existing inequalities. There is no credible pathway to net zero transport that bypasses social justice.

Accounting for future costs: climate and resilience

Another limitation of current approaches is how future impacts are assessed. While appraisal frameworks consider emissions and discount future costs, this can undervalue long-term climate effects and mitigation measures. 

Without adaptation the cost of climate change to public welfare is predicted to rise to between 1-5% of UK GDP by 2050 under a 2°C global warming level, equivalent to £60-£260 billion per year (CIHT, 2026).

Phil Blythe CBE  FREng  CEng  FIET  FCIHT, Professor of Intelligent Transport Systems, Head of Future Mobility Group, Director of DARe – National Hub for Decarbonised, Adaptable and Resilient Transport Infrastructures at the Civil Engineering and Geospatial Engineering, School of Engineering at Newcastle University has also emphasised through Newcastle University’s work in the DARe Hub, the societal cost of climate-related infrastructure failure is often far greater than it first appears and is still not fully recognised in policy and appraisal.
Climate change is not just an abstract future cost - it has tangible implications for transport systems, including:

• Increased flooding and disruption
• Changing infrastructure design requirements
• Impacts on supply chains and accessibility

Crucially, the cost of adapting to these effects - such as flood defences or infrastructure resilience - is often not fully reflected in current models. Newcastle University’s contribution to the Department for Transport’s 2025 Adaptation Strategy also underlines the importance of explaining these risks clearly to the public, using accessible supporting material to build wider understanding of hazard impacts. A more comprehensive understanding of “true cost” would therefore include:

• The future cost of climate impacts
• The cost of mitigation and adaptation measures
• Wider systemic risks affecting transport networks

Place matters: the need for localised solutions

One of the most consistent findings from the interviews is that transport solutions - and their associated costs - are highly context-dependent.
What works in a dense urban centre may not be appropriate in rural or low-density areas. For example:

• Fixed-route public transport can be viable in cities but struggles in dispersed communities
• Rural areas often rely heavily on private car use due to limited alternatives

Emerging approaches such as demand-responsive transport demonstrate potential in addressing these challenges, particularly when supported by digital tools and data. 
Professor Macdonald illustrated this with the example of SOAST. “Suburban Fringe on-Demand Algorithm based Shared Transport”. The project aimed to provide much-needed transport in lower-density areas by combining parcel delivery with on-demand shared passenger services, enabling travel from any postcode to any other postcode.

However, these systems often require subsidy and careful design to ensure they deliver value - highlighting again the importance of understanding wider social benefits, not just financial viability.

This also points to the importance of moving beyond macroscopic, one-size-fits-all approaches towards more nanoscopic and decentralised forms of analysis and intervention. Transport barriers and opportunities vary not only between regions, but between cities and even neighbourhoods. An older industrial city such as Sunderland may face very different mobility, safety and access issues from Cambridge or London. If appraisal and policy remain too aggregated, they risk missing the local detail that determines whether interventions succeed. More decentralised, context-sensitive planning - supported by granular data and local knowledge - is therefore essential if the sector is to design solutions that are equitable as well as effective (Malik, n.d.; Malik, Dala and Busawon, 2022).

The implication for policy is that nationally uniform approaches are unlikely to succeed. Instead, there is a need for:

• Place-based strategies
• Locally tailored interventions
• Greater community involvement in scheme design

Harnessing data to better understand value

Advances in data collection and analytics present new opportunities to better quantify the true cost of transport. Sources such as mobile phone data, journey planning apps and telematics can provide insights into:

• Travel behaviour
• Mode choice
• Accessibility patterns
• Social interaction and wellbeing

While access to such data remains constrained in some contexts, according to Professor Macdonald its potential to support more evidence-based decision-making is significant. Importantly, this could allow appraisal frameworks to incorporate previously intangible factors, such as community cohesion, user experience, and health and wellbeing - an area that Newcastle University has identified as a key theme in its Mobility and Transport work.

Towards a more holistic framework

The concept of the “true cost” of transport is evolving. The interviews highlight a broad consensus that existing frameworks, while robust in many respects, are not yet fully capturing the complexity of modern transport systems. They also reinforce the importance of stronger engagement with government, universities and sector partnerships so that the transport system can respond more effectively and earlier to the challenges of decarbonisation, resilience and social equity.

A more complete approach would:

• Explicitly integrate social equity and intersectionality alongside economic efficiency
• Better account for long-term climate impacts and mitigation costs
• Reflect local context and variation in needs
• Incorporate new data sources to understand behaviour, safety and outcomes at a more granular level
• Capture wider societal benefits, including health, wellbeing and community cohesion
• Ensure decarbonisation measures are designed around fairness, accessibility and public legitimacy

Conclusion

Transport is more than a system for moving people and goods - it is a fundamental enabler of opportunity, inclusion and quality of life. As the sector faces the twin challenges of decarbonisation and societal change, understanding its true cost becomes increasingly important.

Moving beyond narrow economic metrics towards a more holistic, evidence-based approach will be essential. Doing so will not only improve decision-making but also help ensure that transport systems deliver benefits that are fair, sustainable and aligned with wider societal goals. It will also require a clearer understanding of whether the sector is on track towards decarbonisation, recognising that delaying action until the final years before 2050 would result in far greater cumulative emissions.

Put simply, if the sector is serious about understanding the true cost of transport, it must recognise that environmental sustainability and social justice are not competing aims - they are mutually dependent.

References

Chartered Institution of Highways and Transportation (CIHT) (2024a) Ensuring a Just Transition to Net Zero Transport: Policy Brief. Available at: https://www.ciht.org.uk/knowledge-resource-centre/resources/policy-technical/ensuring-a-just-transition-to-net-zero-transport-policy-brief/  .

Chartered Institution of Highways and Transportation (CIHT) (2024b) Charging for Road Use: What is the Future of Mobility Pricing? Available at: https://www.ciht.org.uk/knowledge-resource-centre/resources/policy-technical/charging-for-road-use-what-is-the-future-of-mobility-pricing/charging-for-road-use-white-paper-access/ 

Chartered Institution of Highways and Transportation (CIHT) (2026) ‘CIHT and CCC collaborate to share findings from a Well Adapted UK’, 21 May. Available at: https://www.ciht.org.uk/news/ciht-and-ccc-collaborate-to-share-findings-from-a-well-adapted-uk/ 

Gandhi, I. (1972) ‘Man and environment’, speech delivered at the United Nations Conference on the Human Environment, Stockholm, 14 June. Available at: https://archive.org/stream/indira-gandhi-one-earth-one-environment-one-humanity-14-june-1972/Indira%20Gandhi_One%20Earth%20One%20Environment%20One%20Humanity_14June1972_djvu.txt 

Malik, F.A. (n.d.) ‘Intelligent real-time modelling of rider personal attributes for safe last-mile delivery to provide mobility as a service’. Available at: https://napier-repository.worktribe.com/output/4248182/intelligent-real-time-modelling-of-rider-personal-attributes-for-safe-last-mile-delivery-to-provide-mobility-as-a-service

Malik, F.A. and Dala, L. (2022) ‘Intelligent nanoscopic cyclist crash modelling for variable environmental conditions’, conference paper. Available at: https://napier-repository.worktribe.com/output/4247803/intelligent-nanoscopic-cyclist-crash-modelling-for-variable-environmental-conditions

Malik, F.A., Dala, L. and Busawon, K. (2022) ‘Real-time nanoscopic rider safety system for smart and green mobility based upon varied infrastructure parameters’, Future Internet, 14(1), p. 9. Available at: https://napier-repository.worktribe.com/output/4248151/real-time-nanoscopic-rider-safety-system-for-smart-and-green-mobility-based-upon-varied-infrastructure-parameters

Malik, F.A., Egan, R., Dowling, C.M. and Caulfield, B. (2023) ‘Factors influencing e-cargo bike mode choice for small businesses’, Renewable and Sustainable Energy Reviews, 178, 113253. Available at: https://napier-repository.worktribe.com/output/4248213/factors-influencing-e-cargo-bike-mode-choice-for-small-businesses 

United Nations Framework Convention on Climate Change (UNFCCC) (n.d.) ‘The Kyoto Protocol’. Available at: https://unfccc.int/process-and-meetings/the-kyoto-protocol 

CIHT CLIMATES was published a year ago, this is part of a short series to update CIHT members and sector around the latest thinking on CIHT CLIMATES in 2026.