If you're thinking of enlisting in the military, start with some research. It's a big decision, and you’ll have important choices to make when you sign up.
As an active duty enlisted member, you'll learn a job specialty and do hands-on work. You’ll sign a contract, usually for four years active and four years inactive service.
The military has five branches: the Air Force, Army, Coast Guard, Marine Corps, and Navy. Each has its own focus, job specialties, base locations, and more.
Requirements to Enlist
U.S. citizen or
Lawful permanent resident with a valid Green Card (You may have fewer job choices.)
Enlist at 17 with parental consent, or 18 or older without. Each service has a different enlistment age limit:
Coast Guard: 31
Air Force: 39
Education and Testing
High school diploma or
GED (Your options may be more limited in some branches.)
Everyone must take the Armed Services Vocational Aptitude Battery (ASVAB) test. It determines which branches and jobs you can pursue.
Health and Fitness
Pass a physical exam and meet weight limits. Each service has different fitness standards.
Steps for Enlisting
1. Contact a Recruiter
Get in touch with a recruiter for each branch you’re interested in. They’ll answer your questions.
2. Report to MEPS
If you decide to enlist, you'll spend a day at a military entrance processing station (MEPS). You'll take the ASVAB, have your physical exam, and meet with a career counselor. If you're accepted, you'll take the oath of enlistment.
3. Await Orders for Basic Training
You'll receive orders for basic training within a few weeks. If you enrolled in the delayed entry program, you’ll get orders within a year.
To learn more and to find a recruiter, go to usa.gov/join-military.
Join the Military as an Enlisted Member
Enlisted members make up most of the military workforce. They receive training in a job specialty and do most of the hands-on work. Usually, you’ll sign up for four years of active duty and four years inactive. After you’ve completed your active duty time, you can either extend your contract or re-enlist if you want to continue serving.
Officers make up a much smaller part of the workforce. To join as an officer, you typically must have a four-year college degree and complete an officer program. You compete for promotion to continue your career. Most officers are managers who plan and direct operations. Others are professionals like doctors and lawyers. Officers get paid more than enlisted members and enjoy certain other benefits.
You don’t have to join as an officer to become one though. You can join as an enlisted member and attend officer training later on.
Requirements for Joining the Military
The U.S. military has five branches of service: the Army, Navy, Air Force, Coast Guard, and Marine Corps. The requirements to join are similar for all five. The main differences are in age limits, test scores, and fitness levels. Men and women meet different fitness standards. Besides the requirements listed here, a branch may have other requirements.
Age Limits for Enlisting
You must be at least 17 to enlist in any branch of the active military. The oldest you can be to enlist for active duty in each branch is:
Coast Guard: 31
Air Force: 39
Some branches have different age limits for their part-time Reserve and National Guard. Visit each service's recruiting website for its part-time age limits.
Requirements for Enlisting If You Are Not a U.S. Citizen
You do not have to be a U.S. citizen to enlist in the military, but you may have fewer options. If you are not a U.S. citizen, you must:
Each service has its own physical requirements and fitness standards. These depend on the demands of its mission. Even within the same branch, some jobs have tougher or extra requirements.
Steps for Joining the Military
Start by doing some research about your options for joining the military. Learn about the five active-duty branches and their part-time counterparts. Know the main differences between officers and enlisted members.
Once you know which branch you’re considering, contact a recruiter. A recruiter will give you an overview and answer your questions about that service. If you’re interested in more than one branch, contact a recruiter for each. If you’re interested in joining as an officer, the recruiter will explain any options you may be eligible for.
If you decide to enlist, you will report to a military entrance processing station (MEPS). You’ll spend a day or two completing pre-enlistment steps. These include taking the ASVAB, having a physical exam, meeting with a career counselor, and if you’re accepted,taking the oath of enlistment. From there you’ll receive orders for basic training, usually to start within a few weeks. If you enrolled in a delayed entry program, you’ll go home and get orders for basic training within a year.
Commissioned officers are the military’s managers and highest-ranking leaders. They oversee plans, direct operations, give orders, and command units. Some are doctors and lawyers. They typically have at least a bachelor’s degree.
Officers have authority over enlisted members. They have broader responsibilities and accountability. But they rely upon enlisted members’ technical skills and experience to get the job done.
Junior officers may lead platoons and command patrol boats. But a senior enlisted member is often their second in command.
Officers must get promoted at certain points to remain on active duty. This can be true for enlisted members too. But it is guaranteed for officers at a much earlier stage of their careers. In return for officers’ greater accountability and less job security, they get higher pay and some extra benefits.
United States Merchant Marine Academy - Trains students for military and civilian careers. New graduates have two choices. They can join the Navy or the Coast Guard as an officer. Or they can get a job in the civilian maritime industry at sea or ashore.
Senior military colleges are civilian schools that combine higher education with military instruction. Students can become commissioned officers after graduating. But they only have to join the service if they’re received a military scholarship.
Reserve Officers Training Corps (ROTC)
Colleges and universities nationwide offer the Reserve Officers Training Corps (ROTC) program. The program pays for students’ tuition and prepares them to be military officers. In return, students commit to serving in the military afterward. Each service has its own ROTC program.
Officer Candidate School (OCS)
New four-year college graduates go to Officer Candidate School (OCS) to join as officers. Each service has its own OCS, which lasts around three to four months. Enlisted members can also apply to attend OCS and graduate as commissioned officers.
Direct commission officers are professionals with advanced training who join as military officers. They are usually doctors, lawyers, dentists, engineers, or chaplains.
Contact a recruiter for the service branch you’re interested in to learn more about officer programs:
Warrant officers are officers who advance from the upper enlisted ranks. They stay in their career fields. They rank above enlisted members and below commissioned officers. A Marine Corps E5 can compete for warrant officer. In the Army, Navy, and Coast Guard, you must be an E6. The Air Force doesn't have warrant officers.
Non-commissioned officers (NCO) are higher-ranking enlisted members with demonstrated leadership abilities. Most services consider enlisted members at pay grade E4 to be NCOs. In the Air Force, you are an NCO at E5. The Army has two ranks at pay grade E4 - specialist and corporal. But a corporal is an NCO while a specialist is not.
Infographic: Five Branches of Military Service
The United States armed forces are made up of five service branches, each with a unique mission and place in U.S. military history.
The U.S. military has five branches of service. The Air Force, Army, Marine Corps, and Navy fall under the Department of Defense. The Coast Guard falls under the Department of Homeland Security. Each service has a unique mission, which is reflected in its training, equipment, locations, and military culture.
U.S. Air Force
Mission: "To fly, fight and win in air, space, and cyberspace"
This newest service, created in 1920 as the Army Air Force, became its own military branch in 1947. That same year, it broke the sound barrier.
The Air Force’s space program detects ballistic missile launches, tracks satellites, assists with rocket launches, and more.
Mission: "To deploy, fight, and win our nation's wars by providing ready, prompt, and sustained land dominance…”
The Army conducts major ground combat operations. It uses the most powerful, high-tech weapons, tanks, and fighting vehicles available.
It’s the largest and the oldest service, founded in 1775.
U.S. Coast Guard
Mission: “To ensure our nation's maritime safety, security, and stewardship”
The Coast Guard has 11 official roles. These include search and rescue, drug interdiction, marine environmental protection, and defense readiness.
It's the smallest service, with a budget smaller than the New York subway system.
U.S. Marine Corps
Mission: “As America's expeditionary force...the Marines are forward deployed to win our nation’s battles swiftly and aggressively in times of crisis…”
Marines fight on land, sea, and air. They provide forces and detachments to naval ships and ground operations.
They live by the core values of honor, courage, and commitment, on and off the battlefield. Their motto is “Semper Fidelis,” Latin for “Always Faithful.”
Mission: "To recruit, train, equip, and organize...combat ready Naval forces to win conflicts and wars while maintaining security and deterrence…”
The Navy makes the seas safe for travel and trade.
It’s the largest navy in the world. Its aircraft carriers are like cities, with 5,000 crew members. Its submarines are among the most high-tech vessels in the world.
To learn more and to find a recruiter, go to usa.gov/join-military.
Learn About the Military
Get a brief overview of the five service branches of the U.S. Armed Forces:
U.S. Air Force (USAF)
U.S. Army (USA)
U.S. Coast Guard (USCG)
U.S. Marine Corps (USMC)
U.S. Navy (USN)
The Air Force is part of the Department of Defense (DOD). It’s responsible for aerial military operations, defending U.S. airspace and air bases, and building landing strips. The Air Force Space Command is under this branch. Service members are known as airmen. The reserve components are Air National Guard and Air Force Reserve.
The Army is part of the DOD and is the largest of the five military branches. It handles major ground combat missions, especially operations that are ongoing. The Army Special Forces unit is known as the Green Berets for its headgear. Service members are known as soldiers. The reserve components are Army Reserve and Army National Guard.
The Coast Guard is part of the Department of Homeland Security (DHS). It’s responsible for maritime law enforcement, including drug smuggling. It manages maritime search and rescue and marine environmental protection. It also secures ports, waterways, and the coasts. Service members are known as Coast Guardsmen, nicknamed Coasties. The reserve component is Coast Guard Reserve.
The Marine Corps is part of the DOD. It provides land combat, sea-based, and air-ground operations support for the other branches during a mission. This branch also guards U.S. embassies around the world and the classified documents in those buildings. Marine Corps Special Operations Command (MARSOC) members are known as Raiders. All service members are referred to as Marines. The reserve component is Marine Corps Reserve.
The Navy is part of the DOD. It protects waterways (sea and ocean) outside of the Coast Guard’s jurisdiction. Navy warships provide the runways for aircraft to land and take off when at sea. Navy SEALs (sea, air, and land) are the special operations force for this branch. All service members are known as sailors. The reserve component is Navy Reserve.
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