Colorado has explicit insurance guidance on transgender-related health care.

Regulations:

• 10 Colo. Code Regs. § 2505-10:8.700
  Summary:

  In Federally Qualified Health Centers and Women’s Health Services, patients with a clinical diagnosis of gender dysphoria are eligible for the transgender services benefit, subject to the service-specific criteria and restrictions detailed in section 8.735.5

• 10 Colo. Code Regs. § 2505-10:8.735
  Summary:

  It covers a select number of gender affirming procedures, subject to the service-specific criteria and restrictions detailed in Section 8.735.4, but does not include facial gender confirmation surgeries.

Bulletins and Announcements:

• Bulletin: Bulletin No. B-4.49, Insurance Unfair Practices Act Prohibitions on Discrimination Based on Sexual Orientation (2013)
  Issued by: Colorado Department of Regulatory Agencies, Division of Insurance
  Issued on: March 18, 2013
  Summary:

  Interprets insurance non-discrimination law to prohibit the denial, exclusion, or limitation of “coverage for medically necessary services . . . if the item or service would be provided based on current standards of care to another individual without regard to their sexual orientation,” which is defined in Colorado to include “transgender status.”