This paper discusses the impact that tolling schemes with a higher degree of differentiation of tariffs
among demand categories can have on road demand. The question addressed in the paper is whether the
differentiation of inter-urban road tolls can help to manage demand and meet targets like alleviating
congestion, reducing emissions or making feasible project financing schemes, where toll revenues are
used to cover construction and operating costs. The paper is mainly based on the results of the
DIFFERENT research project, co-funded by the European Commission DG TREN, where a number of
modelling tests have been carried out using two different transport network models. Based on modelling
results we conclude that a trade-off between alternative targets of toll differentiation exists and that results
vary according to the specific context of the application. In non-congested corridors charge differentiation
can raise money, but there is little room for social benefits, whereas in congested areas travel speed on the
road network can be improved by introducing charges on congested non-motorway links. Additionally,
achievement of benefits from differentiated charges may require the co-ordinated introduction of charges
on ordinary roads as well as on motorways.
