In 1975, South Australia became the first state or territory in Australia to legalize homosexuality.

Same-sex marriage has been legal in Australia since 9 December 2017. The legislation to allow same-sex marriage, the Marriage Amendment (Definition and Religious Freedoms) Act 2017, passed the Australian Parliament on 7 December 2017 and received royal assent from the Governor-General the following day.

In South Australia, there are no laws restricting the discussion or promotion of LGBTQ+ topics.

Proof of surgery is no longer required. Instead, individuals are asked to provide a statement from a medical professional or a psychologist certifying that they underwent the appropriate treatment to change their legal gender.

Australian youth outside of Queensland can begin accessing puberty blockers at the age of 10, full HRT is not typically prescribed until 16 and GCS is often not done until 18. However, nobody can access irreversible treatment until 15.

For Oestrogen or Testosterone two independent child and adolescent psychiatrists must do a standardised assessment of psychological development as well as a formal assessment of the child’s gender identification and capacity to understand the proposed treatment. A paediatric endocrinologist establishes the child’s pubertal stage, excludes disorders and discusses with the child and parents the effects and risks of puberty suppression.

For Puberty blockers a young person requires a multidisciplinary team consisting of a paediatrician, two mental health professionals (one must be a psychiatrist), and a fertility expert, to agree treatment is in the child’s best interests. It is then necessary to make an application to the Family Court for authorisation of treatment.

Individuals can request an X gender marker on their documents.

In 1990, amendments to South Australia's Equal Opportunity Act came into effect, adding sexuality, which included "transsexuality", as a protected characteristic from discrimination in all areas.

Trans people would later be redefined under chosen gender in 2009 and gender identity in 2016.

In 1990, amendments to South Australia's Equal Opportunity Act came into effect, adding sexuality, which included "transsexuality", as a protected characteristic from employment discrimination.

Trans people would later be redefined under chosen gender in 2009 and gender identity in 2016.

In 1990, amendments to South Australia's Equal Opportunity Act came into effect, adding sexuality, which included "transsexuality", as a protected characteristic from housing discrimination.

Trans people would later be redefined under chosen gender in 2009 and gender identity in 2016.

In 2017, South Australia's legislation to allow same-sex couples to adopt came into effect.

No territory or state besides the Australian Capital Territory has banned intersex infant surgery.

In 2010, Australia lifted its ban on transgender people serving in the military.

In Australia sexually active LGBT people are unable to donate blood unless they abstain from sex for three months. Since 2021, the deferral period within Australia was reduced from 1 year to 3 months without PrEP.

In June 2023, the Therapeutic Goods Administration (TGA) approved a submission from Australian Red Cross Lifeblood calling to remove most sexual activity ineligibility criteria for plasma donors.

On April 1, 2025, a law passed in South Australia banning the practice and promotion of conversion therapy took effect.

Homosexuality was decriminalised in South Australia in 1975 with an equal age of consent.