Background: Toe-to-thumb transfer has become the gold standard for thumb reconstruction, but in badly mutilated hands, additional soft tissue coverage may be required or a suitable recipient artery may not be available. There are only 3 case reports describing the successful use of a reverse radial forearm flap for coverage of a soft tissue defect around the thumb as well as providing arterial inflow for a toe transfer, performed either simultaneously or secondarily. Methods: A single surgeon's experience of all toe-to-hand transfers performed in conjunction with a reverse radial forearm flap between 1995 and 2014 was reviewed, including patient demographics, type of toe transfer and vascular pedicle, whether immediate or secondary, follow-up, and complications. Results: Eight toe-to-hand transfers were performed in 7 patients-3 children (age range, 3-15 years) and 4 adults (age range, 19-39 years). Three patients underwent primary toe-to-thumb transfer simultaneously with a reverse radial forearm flap, and 5 patients underwent secondary toe-to-hand transfer between 4 months and 2½ years after an initial reverse radial forearm flap. All toe transfers survived completely. Average follow-up was 5.1 years. All patients were satisfied with the function and appearance of their reconstructed thumb. Conclusion: The reverse radial forearm flap is a very reliable procedure as a "Sister" or "Siamese" flap to provide immediate arterial inflow to a simultaneous toe-to-thumb transfer, or to provide primary soft tissue coverage on the radial aspect of the hand and subsequently provide a recipient arterial inflow for a secondary toe transfer.