The I Marine Expeditionary Force is a Marine Air Ground Task Force (MAGTF) of the United States Marine Corps primarily composed of the 1st Marine Division, 3rd Marine Aircraft Wing, and 1st Marine Logistics Group. It is based at Marine Corps Base Camp Pendleton.
3rd Battalion 11th Marines (3/11) is an artillery battalion comprising three firing batteries, a Liaison Unit, and a headquarters battery. The battalion is based at the Marine Corps Air Ground Combat Center Twentynine Palms, California and its primary weapon system is the M777 lightweight howitzer with a maximum effective range of 25 miles. They fall under the 11th Marine Regiment and the 1st Marine Division.
1st Battalion 1st Marines is an infantry battalion in the United States Marine Corps based out of Camp Pendleton, California, consisting of anywhere from 800 to 2,000 Marines and Sailors, but the number fluctuates depending on the Battalion's mission. They fall under the command of the 1st Marine Regiment and the 1st Marine Division. Commonly referred to as "The first of the First."
The 1st Tank Battalion was an armor battalion of the United States Marine Corps which was based out of the Marine Corps Air Ground Combat Center Twentynine Palms, California. It last fell under the command of the 1st Marine Division and I Marine Expeditionary Force. The unit was decommissioned in May 2021 as part of the service Force Design 2030 initiative which saw it move away from larger armor formations.
The 1st Marine Logistics Group is a logistics unit of the United States Marine Corps and is headquartered at Marine Corps Base Camp Pendleton, California, with several subordinate elements also located at Marine Corps Air Station Yuma and Marine Corps Air Ground Combat Center Twentynine Palms.
3rd Battalion 6th Marines is an infantry battalion in the United States Marine Corps based out of Camp Lejeune, North Carolina. Also known as "Teufelhunden", it consists of approximately 1000 Marines and Sailors. They fall under the 6th Marine Regiment and the 2nd Marine Division.
Radio Battalions are tactical signals intelligence units of Marine Corps Intelligence. There are currently three operational Radio Battalions in the Marine Corps organization: 1st, 2nd, and 3rd. In fleet operations, teams from Radio Battalions are most often attached to the command element of Marine Expeditionary Units.
2nd Battalion, 3rd Marines (2/3) was an infantry battalion in the United States Marine Corps based out of Marine Corps Base Hawaii consisting of approximately 1,000 Marines and sailors. The battalion fell under the command of the 3rd Marine Regiment and the 3rd Marine Division. The battalion was deactivated in January 2022 as part of the Marine Corps' ongoing Force Design efforts.
1st Battalion 11th Marines (1/11) is an artillery battalion comprising four firing batteries and a Headquarters battery. The battalion is stationed at the Marine Corps Base Camp Pendleton in California. Its primary weapon system is the M777 lightweight howitzer. The battalion is under the command of the 11th Marine Regiment, part of the 1st Marine Division.
2nd Battalion of the 11th Marines ("Patriot") is an artillery battalion comprising three firing batteries and a Headquarters Battery. The battalion is stationed at Marine Corps Base Camp Pendleton, California. Its primary weapon system is the M777 lightweight howitzer. The battalion was the first in the Marine Corps to fully transition from the M198 Howitzer. They fall under the command of the 11th Marine Regiment and the 1st Marine Division.
5th Battalion 11th Marines (5/11) is a High Mobility Artillery Rocket System (HIMARS) battalion consisting of four Firing Batteries and a Headquarters Battery. The battalion is stationed at Marine Corps Base Camp Pendleton, California. It is the first active duty HIMARS Unit in the Marine Corps. They fall under the command of the 11th Marine Regiment and the 1st Marine Division. This is the only battalion in the 11th Marine Regiment not using the M777A2 lightweight howitzer.
3rd Assault Amphibian Battalion is one of two active duty assault amphibian battalions in the United States Marine Corps. The battalion's primary weapon system is the Amphibious Assault Vehicle or AAV. The AAV is a 27.5-ton armored vehicle that carries up to 21 combat-loaded Marines and is armed with the UGWS, which mounts a .50 cal (12.7 mm) M2HB machine gun and a Mk-19 40 mm grenade launcher. The battalion is also equipped with the Amphibious Combat Vehicle or ACV, a rather new variant to the USMC’s amphibious armament which will replace the AAV in years to come. The AAV ACV are the only armored vehicles in the U.S. inventory that are fully capable of operations both on land and in the ocean. The battalion is part of the 1st Marine Division and the I Marine Expeditionary Force. The unit is based in Camp Pendleton, California.
4th Assault Amphibian Battalion is a mechanized battalion of the United States Marine Corps Reserve. Their primary weapon system is the AAV-P7/A1 Amphibious Assault Vehicle and they are part of the 4th Marine Division of the Marine Forces Reserve. The unit is based out of Tampa, Florida, with subordinate units in Florida, Virginia and Texas.
The 9th Marine Regiment was an infantry regiment of the United States Marine Corps. Formed during World War II, it served until 1994, when it was deactivated during the post Cold War drawdown. Battalions of the Ninth Marine Regiment, but not the regiment itself, were reactivated from 2007 to 2014 as part of the Marine Corps' growth during the wars in Iraq and Afghanistan. The battalions have subsequently been deactivated again.
The 1st Battalion 9th Marines (1/9) was an infantry battalion of the United States Marine Corps. Formed during World War I, it served until the mid-2000s when it was deactivated to make room for one of three light armor reconnaissance battalions. During the Vietnam War, 1/9 sustained an especially high casualty rate, such that it received the nickname "The Walking Dead".
The 7th Engineer Support Battalion is an engineering support unit of the United States Marine Corps and is headquartered at Marine Corps Base Camp Pendleton, California. The unit falls under the command of 1st Marine Logistics Group and the I Marine Expeditionary Force.
The 9th Engineer Support Battalion is a general and direct engineering support unit of the United States Marine Corps and is headquartered at Camp Hansen, Okinawa, Japan. The unit is subordinate to the 3rd Marine Logistics Group and the III Marine Expeditionary Force.
1st Battalion 12th Marines (1/12) was an artillery battalion comprising three firing batteries and a Headquarters Battery. The battalion was stationed at Marine Corps Base Hawaii and fell under the 12th Marine Regiment and the 3rd Marine Division. It was deactivated on 26 May 2023.
The Combat Assault Battalion was a mechanized battalion of the United States Marine Corps and subordinate element of the 3rd Marine Division and the III Marine Expeditionary Force. The unit was last based at Camp Schwab, Okinawa, Japan.
3rd Force Reconnaissance Company is a force reconnaissance unit of the United States Marine Corps Reserve. The company is located in Mobile, Alabama.
United States of America 
United States Marine Corps 
