Purpose: Road haulage has been the most widely used mode of freight transport in many European countries for several decades. Given the attention to sustainable transport in this century, the railroad combined transport may result to be a good alternative, under specific conditions, to road haulage. This paper analyses the main conditions to make the option competitive, using a simplified method useful for the stakeholders involved in decision processes. Method: Relevant cost items have been identified since previous studies available in literature. The proposed formulas consider the different phases of transport chain and have been used to investigate such parameters as the external costs and the location of terminals. Results: If the pre-and post-phases are too long or simply too onerous, the economic advantages of the rail section may not be sufficient to guarantee the convenience of the combined transport. It can be economically competitive over long distances, even when the drayage covers greater distances. Conclusions: The method has been used to examine those situations, in terms of distance covered and frequency of the service, in which railroad combined transport can be cost-effective as an alternative to the full-road solution. The obtained range can be reviewed based on the services, such as shuttle trains to connect seaports with dry ports: the short distance covered may be more convenient due to the high quantities of goods as well as the fixed train composition and path allocation, which means lower terminal cost and times. Finally, some innovative proposals have been introduced.