Unlike the H1, which is a true off-road vehicle the H2, H3 and H4 are SUVs. As of 2006, Hummer has gone international with selected importers and distributors in Europe and other markets. On May 12, 2006, GM announced it would cease production of the original H1 Hummer. There are three current and possibly two future models in the Hummer line: Production models: Hummer H1 (discontinued), Hummer H2, Hummer H2 SUT, Hummer H3, Hummer H3t, Hummer H3x, Hummer H3 Alpha, Concept vehicles: Hummer HX.

The Hummer H1 is basically a HMMWV built for civilian use; it has no armor or weapons fittings. However the powertrain, chassis, body, suspension, etc., are the same. The H1 differs from the HMMWV in having a civilian interior, including trim, comfortable seats, stereo radio, and air conditioning as standard options. As a result of its commercial use, features introduced in the civilian Hummer have been incorporated into improved military versions. The H1's electrical system is 12-volt, with the two batteries wired in parallel. The HMMWV runs on a 24-volt system, where the two batteries are run in series. Since all Hummer vehicles have heavy-duty capabilities, they have been employed by owners for aid in large disaster situations. Hummer Owners Prepared for Emergencies (HOPE) was created by the efforts of The Hummer Club, INC. and the American Red Cross. Together, the two organizations train Hummer owners with CPR and First Aid skills, and basic off-highway skills so that they may assist victims during a disaster situation.

The Hummer H1 was a civilian off-road vehicle based on the M998 High Mobility Multipurpose Wheeled Vehicle (HMMWV, or Humvee), which was created by AM General. The vehicle was produced from 1992 through 2006, and was the first of what became the Hummer line. The H2 SUV/SUT/Hydrogen is the second vehicle sold under the Hummer marque of General Motors. It is a large truck (lighter and slightly slimmer than the Hummer H1, while slightly longer and slightly taller) with room for six passengers (including driver). The rearmost part of the H2 SUV was modified to a pickup truck bed for the 2005 H2 SUT ("Sport Utility Truck"). The Hummer H2 is also prominently featured on CBS' CSI:Miami, driven mainly by the chief of the Miami-Dade Police Department crime lab (Lt. Horatio Caine, played by David Caruso), as well as three of his colleagues: Detective Calleigh Duquesne (played by Emily Procter), Eric Delko (played by Adam Rodriguez) and Ryan Wolfe (played by Jonathan Togo). The Hummer HX is a concept SUV revealed on 8 January 2008 and manufactured by General Motors. The vehicle is smaller than both the H2 and H3 and is powered by a 3.6 L (219.7 cu in) SIDI V6 that uses E85 FlexFuel.

The Hummer H3 SUV/Tri/x is a vehicle from General Motors' Hummer division, introduced in 2006. The H3 is the smallest of the three Hummer models, and though the H3 concept car was a pickup truck, and currently introduced as a conventional SUV, with a future model close to the concept being planned to be launched in the third quarter of 2008. Its GMT345 platform is based on the GMT355 which underpins the Chevrolet Colorado and GMC Canyon pickup trucks. The H3 is built at GM's Shreveport, Louisiana factory. Export versions will also be produced at the General Motors South Africa facility in Struandale, Port Elizabeth, South Africa. H3x Introduced a the 2006 North American International Auto Show, the H3x is a trim update to the Hummer, among the additions were chrome and body-colored parts to differentiate it from the standard edition. The H3x trim package can be combined with the new Alpha package. The Hummer H3T was a concept vehicle from Hummer - mainly used as a media diversion from the Hummer H3 which was to be released in mid 2005. The H3T had two doors and a pickup-style bed. Hummer has also been working with Nike to develop the tires and interior leather appointments. The M998 High Mobility Multipurpose Wheeled Vehicle (HMMWV or Humvee) is a military 4WD motor vehicle created by AM General. It has largely supplanted the roles formerly served by the M151 1/4 ton MUTT, the M561 "Gama Goat", their M718A1 and M792 ambulance versions, the CUCV, and other light trucks with the United States military, as well as being used by a number of other countries and organizations. Humvees were originally also referred to as Hummers, though that term was later reserved for a civilian SUV based on the Humvee.