Transport networks are essential for the growth of any economy or society as they connect people to jobs, schools, hospitals, and to other social activities. However, transportation accounts for approximately 64% of global oil consumption, 27% of overall energy consumption, and 23% of global energy-related carbon dioxide (CO2) emissions (Mead 2021). Globally, motor vehicle pollution is directly responsible for over 185 000 deaths, while road traffic crashes kill an estimated 1.3 million people annually (WHO 2018). Consequently, addressing urban transport challenges is of utmost importance to promote the sustainable growth of cities, balancing the need for connectivity with environmental and public health considerations.

The choice of a transport mode is one of the most essential aspects of urban transport planning and policy as it impacts the overall efficiency with which residents can travel in urban areas (Duleba, Moslem & Esztergár-Kiss 2021; Ort´uzar & Willumsen 2011). Travel mode share or mode split is defined as the proportion of people using a particular mode of transport and is typically presented as a percentage of each mode (McCann 2015). It can be based on a variety of factors, such as the proportion of travellers using a certain mode of transportation, the percentage of trips taken or the distance travelled using a particular mode of transportation (Fountas et al. 2020).

Many developing cities are experiencing a rapid and unplanned growth, which is placing tremendous strain on their transport systems (Mwale, Luke & Pisa 2022). In recent decades, developing cities have experienced high rates of motorisation, and this trend is expected to continue in the future (Thondoo et al. 2020). Predictions estimate that the number of vehicles will increase three- or four-fold, especially in developing nations, between 2005 and 2050 (Mead 2021). The environmental and social impacts of growing motorisation are significant and directly related to quality of life and urban productivity.

Lusaka’s passenger transit system comprises a mix of private vehicles, public buses, taxis, motorcycles, and bicycles. Specifically, the public transport network in Lusaka includes minibuses, buses, and taxis. Minibuses, ubiquitous in the city, accommodate 12–15 passengers along predefined routes, while larger 25–30 seater buses serve designated city routes (Ngoma & Phiri 2016). The determination of bus routes for both minibuses and buses is influenced by a combination of supply and demand dynamics, as well as the presence of sufficient transport infrastructure. Taxis offer personalised travel and comfort for 3–4 passengers, although overcrowding is possible in larger vehicles. These taxis can be licensed, metred vehicles operated by registered companies or unlicensed, informally run taxis using private cars. The popularity of ride-hailing taxi services has soared because of their transparent pricing and convenience. Notably, unlike many other African cities, motorbikes are not widely utilised for public transport in Lusaka (Krasholucka 2022).

The transport environment in the city is fraught with various problems such as the use of shared road space by mixed-modes, traffic congestion, road traffic crashes, poor road infrastructure, and inadequate enforcement of traffic regulations (GRZ 2019a). Formalised public bus services frequently lack reliability, comfort, and safety, thereby failing to adequately meet the transportation requirements of residents (Chikuba 2014): a situation that has led to a rise in the informal or paratransit services, which often lack consistency and safety features (Pojani & Stead 2015). Furthermore, the continued horizontal growth, or urban sprawl, of Lusaka city, is becoming a major cause of the increase in travel distances (Mahendra & Karen 2019). This phenomenon discourages people from utilising non-motorised transport modes such as walking and cycling and has resulted in an increased demand for public transport services as well as private motorised transport (Kakar & Prasad 2020). To deal with the growing problem of traffic congestion, city authorities in Lusaka have embarked on massive road infrastructure improvement projects, which include the expansion of existing roads and the construction of flyovers (Mutumweno 2021). However, the development of transport infrastructure that prioritises the use of motor vehicles leaves very little room for the introduction of alternative modes that tend to reduce the share of other modes of transport (Litman 2011).

In light of the rapid urbanisation and increasing mobility challenges faced by cities in the Global South, understanding travel mode preferences and the factors influencing them in Lusaka, Zambia, becomes crucial. This study examines the travel mode choices and factors influencing the use of these modes among residents of Lusaka for their work or school trips. Additionally, it aims to explore the key challenges faced by users of each travel mode. This research contributes to the existing body of literature by offering unique insights into the travel behaviours and decision-making patterns of Lusaka’s urban dwellers. This study aims to contribute valuable insights into transportation in African cities, aiding the formulation of context-specific and sustainable urban mobility policies. Understanding the travel behaviours and decision-making patterns of city residents is crucial for effective urban planning and transportation management. By gaining unique insights into how people move within the city, policymakers can tailor transportation infrastructure, services, and policies to better meet the needs of residents. This can lead to improved mobility, reduced congestion, enhanced access to opportunities, and ultimately, a more liveable and sustainable urban environment.

Transportation plays a vital role in the development and functioning of urban areas, particularly in cities in low- and middle-income countries (LMICs) where challenges related to mobility and accessibility are prevalent. The understanding of travel mode share and mode selection among residents is essential for sustainable urban planning and the formulation of effective transportation policies (ITF 2021). Within the context of cities in sub-Saharan Africa (SSA) such as Lusaka, rapid population growth, unplanned urbanisation, and inadequate infrastructure are salient issues. These challenges directly impact transportation systems, leading to further problems including traffic congestion, environmental pollution, a heavy reliance on informal mobility, and poor road safety (Palanivel 2017; Pojani & Stead 2015; World Bank 2022; Mwale et al. 2023). The lack of sufficient and effective transportation infrastructure intensifies these problems, leading to safety hazards alongside the exacerbation of congestion and pollution. Public transportation systems are often ill-equipped to support the needs of burgeoning populations, which fuels congestion and environmental degradation (National Academies of Sciences Engineering, and Medicine 2018).

Expanding on specific transportation challenges, traffic congestion emerges as a significant challenge, with roots traceable to the fast pace of population growth, insufficient infrastructure, and ineffective traffic regulation (Karimi et al. 2022). Specifically, in cities in SSA, such congestion can cause extended travel delays, increase pollution levels, and can impede productivity (Agyapong & Ojo 2018). Escalating air pollution levels lead to the deterioration of air quality and the contamination of water bodies. Additionally, noise pollution, often a by-product of intensive traffic flow, is another environmental problem, causing its own range of health issues and further complicating the challenges faced by urban areas (Moroe & Mabaso 2022). Lusaka, for instance, grapples with air pollution emanating from vehicles and water pollution resulting from inadequate drainage and sewer systems (Mbuzi 2020).

Urban expansion places immense pressure on the already strained infrastructure in developing cities, while informal settlements often lack necessary amenities (Chiwele Lamson-Hall & Shahrukh 2022; Mwamba 2020). Concurrently, the city’s public transportation system is marred by overcrowding and unreliability (Transaid 2021). Overcrowded buses and unreliable services create a daily struggle for residents, impacting their comfort, time management, and overall urban mobility. Residents primarily resort to walking, cycling, and public transportation for their commuting needs (Tucho 2022). Road safety is a significant issue in cities within developing countries. Lusaka, reflecting challenges in other rapidly urbanising areas of the Global South, faces alarming rates of road traffic fatalities and injuries. In 2021, Zambia reported a total of 32 372 traffic crashes and 2163 deaths, with Lusaka province accounting for 55% of crashes (13 774 incidents) and 28% of total fatalities (516 deaths) (Mwale et al. 2023; RTSA 2022). These alarming proportions demand urgent actions to enhance road safety in Lusaka and reduce preventable casualties.

In exploring travel behaviour and mode choice, various theories and concepts have been proposed to explain the decision-making process behind individuals’ choice of transportation modes. The Theory of Planned Behaviour (TPB) suggests that an individual’s intention to use a particular mode is influenced by their attitudes, subjective norms, and perceived behavioural control (Bamberg, Ajzen, & Schmidt 2003; Othmane & Maria-del-Mar 2019). The TPB proposes that positive attitudes, perceived social approval (subjective norms), and a high degree of perceived control over performing the behaviour lead to stronger intentions and increase the likelihood of engaging in that behaviour. This study aims to understand: What factors influence the travel mode choices of Lusaka residents for their work or school commutes, and how do these choices reflect underlying psychological drivers? The TPB provides a framework to explore this research question by examining the attitudes, subjective norms, and perceived behavioural control that underlie Lusaka residents’ transportation decisions. By employing the TPB, the study moves beyond demographic correlations to uncover the psychological motivations and barriers that shape commuting behaviour. This theoretical grounding offers valuable insights for encouraging sustainable transportation through interventions that address attitudes, social norms, and perceived control over travel modes.

Numerous studies have been conducted to understand the determinants of mode choice in urban settings. The selection of travel modes in urban settings exhibits notable disparities between developed and developing cities. Well-established public transportation systems, featuring buses, trains, and subways, characterise densely populated developed cities. These urban environments prioritise sustainable modes such as walking and cycling, facilitated by mixed land use and pedestrian friendly infrastructure (Rode et al. 2017). In sharp contrast, developing cities confront challenges such as traffic congestion fuelled by rapid motorisation, urban sprawl, and underdeveloped road systems. In these contexts, private vehicles, particularly motorbikes and minibuses, dominate the transportation landscape (Agyapong & Ojo 2018; Karimi et al. 2022). Despite both types of cities facing intricate mobility challenges, the nuances of their individual contexts play a pivotal role in shaping distinct travel mode preferences and policy approaches.

In exploring the intricate interplay of demographic and socio-economic factors on travel mode choice, several studies have emphasised the role of variables such as age, gender, income, and education (Li et al. 2015; Mayo & Taboada 2020; Patil, Basu & Rashidi 2020). Research indicates a gender-based pattern in travel choices with women generally preferring more environment friendly options such as walking and public transport, while men are more inclined to use private transport (Abdullah et al. 2022; Goel et al. 2023; Saigal, Vaish & Rao 2021).

However, females also show a significant preference for private cars over cycling (Ye et al. 2020). This can be attributed to safety concerns, social norms, inadequate infrastructure, time constraints, cultural influences, and marketing efforts. Age also influences these choices, notably affecting preferences for private cars and bikes (Ye et al. 2020). These findings highlight the complexity of travel mode choices, influenced by both gender and age. Household characteristics such as income, size, and number of vehicles owned can also significantly affect travel behaviour and mode choice (McCarthy et al. 2017; Taofiki¸ Adebukola & Olufemi 2018). Households with young children tend to use cars more, while those without children are more likely to use public transportation (Ye et al. 2018). Several studies also show that accessibility and availability of transportation modes can critically influence travel mode choice (Christiansen et al. 2017; Singh & Vasudevan 2018; Witchayaphong et al. 2020). An absence of a public transit system or poor-quality services can cause a reliance on other motorised modes.

Apart from demographic and socio-economic factors, travel-specific factors such as distance and time have been found to significantly influence mode choice (Li & Zhao 2015; Patil et al. 2020). For obligatory trips such as work or school, public transit is preferable for its economic benefits. During situations like the coronavirus disease 2019 (COVID-19) pandemic, health implications may cause a shift from public transport to private cars (Aderibigbe & Gumbo 2022). Researchers have found that affordability and availability of public transport can attract ridership (Lekshmi, Landge & Kumar 2016; Minal & Sekhar 2014). Higher income and education levels tend to associate with greater use of private cars, while lower income and education levels correspond to more reliance on public transport and paratransit modes. Factors such as gender, residential selection, household size, presence of children, income, travel distances, and employment status influence car use and ownership (Mwale et al. 2022). Vehicle ownership increases with higher income, employment, and education levels (Dissanayake & Morikawa 2010). In addition, there is a negative correlation between age and stop frequency, which refers to the number of stops or destinations a traveller visits during a specific journey or trip (Guan, Srinivasan & Nielsen 2019). The mode choice for travel in developing countries, particularly for work and school trips, hinges on an interplay of social demographic factors, the availability and accessibility of transport modes, and specifics of the travel. Recognising these relationships is crucial in shaping equitable and efficient transportation policies.

Drawing from the literature review, three key hypotheses emerge regarding travel mode preferences and behaviours in LMICs. Firstly, socioeconomic factors such as age, gender, income, and education are anticipated to exert significant influence, with higher socioeconomic status potentially correlating with increased private car usage. Secondly, the accessibility and availability of transportation modes, particularly public transit, and non-motorised options, are expected to shape residents’ travel behaviours, with inadequate infrastructure possibly leading to greater reliance on motorised transportation. Thirdly, policy interventions targeting public transportation infrastructure, pedestrian and/or cycling facilities, and walkability are anticipated to positively impact sustainable transportation behaviours, potentially shifting preferences towards more environmentally friendly options. These hypotheses provide a foundation for understanding the complexities of travel mode choice in Lusaka’s urban context and highlight the importance of socioeconomic, infrastructural, and policy factors in shaping transportation behaviour.

Despite the breadth of existing research, notable gaps persist in our comprehension of travel mode share and mode selection within cities in SSA, underscoring the necessity for deeper exploration. A limited number of studies have specifically delved into mode share and determinants of mode selection in SSA cities, underscoring the imperative for expanded research to understand the distinct intricacies of travel behaviour within these contexts. These gaps notably encompass the need for a more comprehensive examination of transportation modes, particularly non-motorised transport (NMT) and public transport modes. Furthermore, there is a need for a more comprehensive analysis of the factors influencing mode choice decisions and the effectiveness of policy interventions in promoting sustainable transportation in Lusaka.

This study conducts a detailed examination of travel mode selection among Lusaka’s residents. It offers insights into demographic, socioeconomic, and trip-making characteristics, and their influence on travel behaviour. The study also reports on the mode share proportion for each transportation option, providing a clear perspective on current trends and potentially informing future policy interventions for sustainable transportation in Lusaka.

The research aimed to address the following central question: ‘What is the current mode split for work and school trips, and what factors influence mode selection in Lusaka?’ The study findings highlight the prominence of non-motorised and public transport modes, which account for a substantial proportion of the city’s mobility patterns.

Our study contributes to the understanding of travel behaviours and mode preferences in urban areas, particularly in the Global South. Public buses are the primary mode because of their low cost and accessibility, despite challenges like overcrowding. Walking is also popular, especially for short distances, highlighting the importance of pedestrian-friendly infrastructure. Cycling, although less common, is favoured for longer trips, indicating a potential for promoting cycling as a sustainable mode. Private car usage, while significant, is driven by convenience and flexibility and could be discouraged through policies such as congestion pricing. Differences in transportation preferences are observed based on residential density, with high-density areas relying more on public transport and walking, and low-density areas favouring private vehicles. Socio-demographic factors such as income and education level also influence mode choice, suggesting the need for tailored interventions to promote sustainable transportation. Comparisons with other African cities underscore the importance of active mobility and efficient public transportation for urban mobility across the continent, despite variations in transportation patterns and challenges.

Importantly, our research addresses notable gaps in the existing literature regarding travel mode share and mode selection within cities in the Global South. By providing insights into the transportation patterns and preferences of Lusaka residents, we contribute valuable knowledge for policymaking and urban planning initiatives aimed at fostering sustainable transportation systems. Our study lays the groundwork for future research to delve deeper into these dynamics and assess the effectiveness of policy interventions in promoting sustainable urban mobility in developing cities.

In conclusion, our study offers significant scientific contributions by enriching the understanding of travel behaviours and mode preferences in Lusaka, Zambia, and similar urban contexts. By identifying key factors influencing travel mode selection and highlighting the importance of sustainable transportation policies, our research serves as a catalyst for advancing equitable and environmentally friendly transportation systems in the Global South.