Undoubtedly the most popular variety of the Buffalo nickel series is the 1937-D 3-Legged variety. This erroneous variety occurred in the aftermath of clashed dies, with a mint employee polishing away the damage perhaps too vigorously — the bison’s foremost leg was obliterated in the process. This minting blunder serendipitously created one of the hobby's most famous non-bronze error coins, one well known to many even beyond the numismatic crowd.

While there are no known mintage figures for the 1937-D 3-Legged Buffalo nickel, numismatic experts believe approximately 10,000 survive, with the vast majority of these extant in circulated grades. Interestingly, news of this variety hit the public early on, and many 1937-D 3-Legged Buffalo nickels were pulled from circulation within months of their release, meaning a good deal of the circulated pieces range from XF40 to AU58. Still, fewer than 15% of these coins are known in uncirculated grades, and they are particularly rare above MS64.