A method, system, and computer program product for efficient data transfer using metadata sharing. The method includes: determining difference blocks by comparing a metadata map of a requested file to a pre-existing metadata map at a receiving site, wherein a difference block is a data block the receiving site needs to generate the requested file; mapping the difference blocks in a missing metadata map; transmitting the missing metadata map from the receiving site; and transferring the difference blocks to the receiving site from a plurality of available servers, wherein the difference blocks are transferred to allow for the fastest transmission.