Can a same-sex couple marry? If so, are there any differences from opposite-sex marriages?
Yes. On September 26th, 2021, Swiss citizens widely accepted (64% in favor) the "Marriage for All" legislation, establishing gender-neutral marriage. There is no difference between same-sex and opposite-sex marriages.
PROTECTION
Related questions
Protection
Is either being homosexual or engaging in consensual homosexual sexual acts illegal? If so, what are the penalties?
No. Homosexuality and consensual homosexual acts are legal under Swiss law.
Protection
Is any aspect of gender identity or gender affirming treatment illegal? If so what are the penalties?
No. However, there are specific requirements for minors. See question 37.
Protection
Are there further comments on gender identity and gender affirming treatment in Switzerland?
According to case law, gender-affirming treatments must be reimbursed by basic (and mandatory) health insurance (see Supreme Court 137 I 86). No legal text covers all areas, and concerned individuals might encounter resistance from insurers, requiring additional documentation to establish the necessary diagnosis of Gender Identity Disorder in Adolescents or Adults according to DSM 302.85. Existing psychiatric therapy of at least six months is usually required for insurance coverage of hormonal treatments. Insurers won't cover surgery without an existing psychiatric therapy for at least one year and will usually not accept claims without prior hormonal treatment. Surgery coverage is extensive and may include genital, mammary, facial (though this is disputed), and vocal cord modifications (see Supreme Court 9C_572/2015 § 4.2).
Protection
Are foreign marriages of same-sex couples recognised?
Yes.