UH-1N Iroquois
Initial production model, used by the USAF, USN, and USMC.
Over the years, the primary operators, the USMC has developed a number of upgrades for the aircraft including improved avionics, defenses, and a FLIR turret.
 The USAF planned to replace their UH-1Ns with the Common Vertical Lift Support Platform to support the service's ICBM activities, but also examined a life extension for their current fleet.

VH-1N
VIP transport configuration
HH-1N
SAR variant.

UH-1Y Venom
A UH-1N replacement and upgrade as part of the H-1 upgrade program for the USMC, designed to coincide with a similar upgrade for the AH-1W attack helicopter to AH-1Z Viper standard, with common engines and other major systems.
UH-1N Iroquois
Initial production model, used by the USAF, USN, and USMC. Over the years, the primary operators, the USMC has developed a number of upgrades for the aircraft including improved avionics, defenses, and a FLIR turret.  The USAF planned to replace their UH-1Ns with the Common Vertical Lift Support Platform to support the service's ICBM activities, but also examined a life extension for their current fleet.
VH-1N
VIP transport configuration
HH-1N
SAR variant.
UH-1Y Venom
A UH-1N replacement and upgrade as part of the H-1 upgrade program for the USMC, designed to coincide with a similar upgrade for the AH-1W attack helicopter to AH-1Z Viper standard, with common engines and other major systems.
Bell UH-1N Twin Huey