Same-sex marriage refers to lawful marriage between spouses of the same sex. Same-sex marriage is legal and recognized in every U.S. state and the District of Columbia (Washington, D.C.).

As long as a same-sex couple is married in a jurisdiction with legal authority to authorize the marriage, a health insurance company that offers health coverage to opposite-sex spouses must do the same for same-sex spouses.

The federal Health Insurance Marketplace® also treats married same-sex couples the same as married opposite-sex couples in every state when they apply for premium tax credits and lower out-of-pocket costs on private insurance plans.

In Delaware, same-sex marriage has been legal since July 1, 2013, following the passage of the Civil Marriage Equality and Religious Freedom Act of 2013. This means that same-sex couples have the same rights to marry as opposite-sex couples, and their marriages are recognized under Delaware law. Furthermore, under federal law, specifically the Supreme Court's decision in Obergefell v. Hodges in 2015, same-sex marriage is recognized as a legal right across all U.S. states and territories. Consequently, health insurance companies in Delaware are required to offer the same health coverage benefits to same-sex spouses as they do to opposite-sex spouses. This includes coverage offered by private insurance plans through the federal Health Insurance Marketplace®, where married same-sex couples are treated the same as married opposite-sex couples for purposes of premium tax credits and lower out-of-pocket costs.