Transgender people have served or sought to serve in the United States Armed Forces throughout its history. As of May 8, 2025, transgender individuals are banned from enlisting in and serving in the U.S. military, except under narrow waivers for those who have not undergone gender transition, have maintained stability in their birth sex for at least 36 consecutive months, serve in roles critical to warfighting capabilities, and are willing to adhere to all standards associated with their birth sex. Transgender civilian employees at the DoD and private military companies are not subject to the military ban.

Prior to 1960, there was no formal, explicit policy specifically targeting transgender individuals in the U.S. military, but they were effectively barred from service under broader medical and psychiatric disqualification standards. From 1960 until 2016, transgender individuals were formally banned from serving in the U.S. military. From 2016 to 2017, transgender individuals were allowed to serve openly. From 2018 to 2019, and again from 2021 to 2025, they were allowed to both serve and enlist openly. From 2019 to 2021, transgender individuals were banned from enlisting in and serving in the U.S. military, except under narrow exceptions.

From January 28 to March 27, 2025, the U.S. Navy began rejecting all transgender applicants. Across the rest of the U.S. Armed Forces, transgender enlistment and access to publicly funded gender-affirming surgeries were paused on February 7, 2025, and a full ban on transgender service was implemented on February 26, 2025. These restrictions were paused from March 27, when a nationwide preliminary injunction was issued in the case Shilling v. United States, to May 6, when the U.S. Supreme Court stayed the injunction allowing the ban to resume effect. As of September 2025, the ban is being appealed in the Ninth Circuit.

Unlike bisexuals, gays, and lesbians, whose service was codified by the Don't Ask, Don't Tell Repeal Act of 2010, transgender service and enlistment policies in the U.S. military are not codified in the United States Code. The only statutory provision is the Selective Service System, which requires all transgender women in the United States who were assigned male at birth and are ages 18–25 to register regardless of legal or medical transition, though they would not be drafted if induction were reinstated, provided they can present at least one government document showing their legal gender marker as female.

This absence of codification allows for frequent policy changes via administrative and executive directives, making it a recurring issue of political contention. This dynamic has been described as an example of a political football, with policies frequently revised or reversed depending on the administration in power, resulting in five major transgender U.S. military policy changes across four presidential administrations in less than a decade since June 30, 2016.

History Service in secret (pre–1960) Many women during the American Civil War disguised themselves as men to enlist as soldiers and fight in the war. During this time, women were not legally allowed to fight; however, it is estimated there were more than 400 women who were passing as male soldiers during the war. Many of these female soldiers' true identities were never discovered throughout the time of their service. When enlisting, adult women were often able to pass as teenage boys. The physical examinations were lax, leading to many women able to begin training. There were numerous instances of soldiers' female identities being exposed, usually after having been hurt and sent to a soldiers' hospital. Most often, these women just received medical attention and were sent home. However, in several instances, some women who had been disguised as male soldiers were punished or even imprisoned.

Assigned female at birth, Union Army soldier Albert Cashier enlisted on August 6, 1862. Born in Belvidere, Illinois, his transition to male remained unknown throughout the entirety of his service, and he kept the identity of Albert Cashier for the remainder of his life. It was not until 1911, while working as a handy man, that he was struck by an automobile and fractured his leg. The physician who treated Cashier became aware of his assigned sex at birth. Shortly after the injury, Cashier was admitted into the Soldiers' and Sailors' Home in Quincy, Illinois where, in his application, he gave his birth name, and stated that he was born in Ireland on December 25, 1844. At the home, only the doctor knew that he was transgender, and he was able to continue to live as Albert Cashier along with other patients in the home. When his mental health became too deteriorated for the home to adequately take care of him, he was sent to an insane asylum at Watertown. At the asylum Albert was deadnamed and forced to wear dresses until his death in 1915. Albert Cashier was buried with full military honors and uniform, with his gravestone proclaiming "Albert D. J. Cashier" before his deadname.

In 1952, Christine Jorgensen was the first transgender American woman to undergo gender confirmation surgery after being drafted into the United States Army to serve during World War II. The surgery made front-page news with headlines such as "Ex-GI Becomes Blonde Beauty" from the New York Daily News focusing on her prior military service.

Cold war crackdown (1960–2008)

As early as 1960, Executive Order 10450 was applied to ban transgender individuals from serving in the United States military. On May 17, 1963, gender transitioned or transitioning individuals were officially prohibited from the United States military by Army Regulation 40-501. This policy reasoned transgender people were medically unqualified to serve because their mental state was considered unfit.

In the 1980s, the United States military decided to apply medical regulations more forcefully on those who identified as transgender. In the case Doe v. Alexander (1981), which was about a transgender woman who had been rejected from the United States Army Reserve due to having had gender reassignment surgery, the Army defended their policy of denying enlistment to transsexual persons by stating that supporting transsexuals would raise a medical problem in the form of hormone supplements not always being available for such personnel. Leyland v. Orr (1987) was about Air Force member Leyland, a transgender woman, who underwent a gender reassignment surgery before being discharged. The courts ruled this discharge as valid due to the reasoning that Leyland was indeed unfit physically rather than mentally. This judgement was determined by inferring that genital surgery is similar to an amputation surgery, which leaves the individual unable to meet the demands of a soldier.

Obama administration (2009–2016) 2009–2012 Under Department of Defense Instruction 6130.03, "Medical Standards for Appointment, Enlistment, or Induction in the Military Services" dated July 2, 2012, candidates for military service should not have "[c]urrent or history of psychosexual conditions, including but not limited to transsexualism, exhibitionism, transvestism, voyeurism, and other paraphilias" which is noted as "not a contradiction of the repeal of 'Don't Ask, Don't Tell'" since homosexuality was removed from the list of psychosexual conditions in DSM in 1973.

2013–2014 In 2013, Captain Sage Fox, who had enlisted in the Army 1993 and taken time off after transitioning to the Reserves in 2012 to undergo sex reassignment surgery, was ordered to resume active duty, despite policies blocking the service of transgender personnel. After a review, the military concluded that it could not legally discharge her, so Fox was asked to return and serve again as a woman. This made her the first openly transgender person serving in the military. She served for 2 weeks and then she had orders to be placed on the inactive reserve which she believed was due to her gender identity. She was not granted disability but her medical records did not indicate her unfit to serve. In 2016, Obama repealed the transgender ban in the military and Sage Fox was working with the medical board and was expected to be reenlisted.

On March 13, 2014, an advisory panel organized by the Palm Center, a research institute based at San Francisco State University, released a report that found no compelling medical reason for placing limitations on military service by transgender individuals. It said DoD rules that prevented enlistment or continued service by transgender individuals were based on outmoded and untenable ideas about their psychological and physical fitness, and it dismissed concerns about the costs of medical care. It said the DoD's policies could be changed by an executive order. The panel was headed by former Surgeon General Joycelyn Elders and Rear Adm. Alan Steinman, a former chief health and safety director for the Coast Guard. It concluded:

At the time, service personnel were still being dismissed for being transgender despite their satisfactory job performance. The dismissal policy was based on outdated medical diagnoses which suggested gender nonconformity was a mental illness. In May 2014, Secretary of Defense Hagel said his department's policy with respect to transgender service should be reviewed "continually". Later in May, the ban on Medicare coverage for gender reassignment surgery, which had been in place since 1981, was lifted in response to a lawsuit filed in 2013 on behalf of Denee Mallon, a 74-year-old transgender Army veteran. With the end of the ban on openly gay service members, Air Force Secretary Deborah Lee James stated the ban on transgender personnel "is likely to come under review in the next year or so" in a December interview.

Also in May 2014, the Williams Institute published a research brief estimating 15,500 transgender people were serving on active duty or in the Guard/Reserves, and an additional 134,300 transgender people were either veterans or retired from the Guard/Reserves. The brief was based on a six-month survey of over 6,000 transgender people in 2008–09 asking (in part) if they had ever served in the armed forces, or had been denied entry because they were transgender.

2015

In February 2015, during his first trip as United States Secretary of Defense, Ash Carter was asked about the service of transgender troops, to which he replied:

Days later, the White House echoed Secretary Carter's support of transgender service personnel.

In mid-March 2015, a doctor and major in the United States Army Medical Corps named Jamie Lee Henry became the first known active-duty Army officer to come out as transgender, and the first and only active-duty service member who has changed her name and gender within the United States military, to her knowledge and to the knowledge of other trans activists. In September 2022, Henry and her wife were indicted on conspiracy charges for allegedly attempting to transfer confidential military medical information to Russia.