SIG Sauer created the P226 9mm in the 1980s from the P220 platform. It entered XM9 trials versus the Beretta 92, which the U.S. military picked for lower cost, while Naval Special Warfare adopted the P226 for SEALs over its saltwater resistance, chrome-lined barrel and 30,000-round test performance. The MK25 remained the SEAL standard sidearm from 1989 until 2015 when the Glock 19 took over.

Original versions used a double-action/single-action system with a decocker and 15-round magazines. The latest P226X line incorporates an optics-ready slide inspired by the X-Five and retains the all-metal frame plus proven durability.