Road autonomous mobile robots have attracted the attention of delivery companies and policy makers for their potential to reduce costs and increase urban freight efficiency. Established delivery companies and new startups are investing in technologies that reduce delivery times and/or increase delivery driversβ productivity. In this context, the adoption of Road Automatic (or Autonomous) Delivery Robots (RADRs) has a growing appeal. Several RADRs are currently being tested in the United States. The key novel contributions of this research are: (a) an analysis of the characteristics and regulation of RADRs in the US and (b) a study of the relative travel, time, and cost efficiencies that RADRs can bring about when compared to traditional van deliveries. The results show that RADRs can provide substantial cost savings in many scenarios but in all cases, at the expense of substantially higher vehicle miles per customer served. Unlike sidewalk autonomous delivery robots (SADRs), it is possible the RADRs will contribute significantly to additional vehicle miles per customer served