A cutter rig is a sailboat with a type of sail configuration in which two or more sails are set forward of the mast. These are known as the head sails. A common design for modern cutters contains two head sails, with the inner sail referred to as the stay sail and the outer sail either a jib or genoa. The stay sail is set from the inner forestay, and may be self-tending on its own boom, or “loose footed.” The jib is set from the head forestay and is fixed to either a bowsprit or the bow itself.
Traditionally, the mast on a cutter rig was more centrally located than those on any other single-masted sailboat. This was to allow more room on the bow for multiple head sails. Since the mid 20th-century, however, mast positioning has become mostly irrelevant, and the only distinguishing feature of modern cutter rigs is multiple head sails.
This re-defining of a traditional cutter rig has led to a proliferation of the cutter rig sloop, which is basically a sloop with a retrofitted stay sail boom and an additional forestay. Not all sloops will support these modifications, however. Whether or not the modification is possible is due to the composition of the mast, hull strength, and other factors.
A cutter rig is considered by many sailors to be a more versatile and safer sail configuration. Its versatility has led to its resurgence in popularity among leisure and cruising sailors. If the stay sail is self-tending and can be controlled from the cockpit, short-tacking upwind becomes much easier than with a sloop rig, especially when single-handing.
Of course, in light winds the extra sail area is of some benefit, but the boat is also easier to handle if winds increase suddenly. The stay sail will keep the boat controlled while the other head sails and the main sail are reefed. With the main sail completely reefed, a cutter rig running on its stay sail makes for an ideal heavy-weather craft. When running straight downwind, the extra sail also acts as a roll stabilizer, a feature not available with other sail configurations.
On the downside, when tacking with a large jib on a cutter rig, the sail must pass through the narrow space between the inner forestay and the head forestay. This can be alleviated in some modern cutter rigs with a removable inner forestay. Also, a cutter rig is not considered as fast under most conditions as a sloop rig, which tends to make it unpopular with racing sailors.