By this time construction of the MR extension from London to Aylesbury was underway, and on 1 July 1891 the MR absorbed the Aylesbury and Buckingham Railway.
På dette tidspunkt var byggeriet af MR forlængelsen fra London til Aylesbury godt i gang og den 1. juli 1891 overtog MR formelt Aylesbury and Buckingham Railway.