What does the D2 mean on medicare card?

The "D2" designation on a Medicare card typically indicates that the individual is eligible for Medicare due to a disability. This designation is used for beneficiaries who qualify for Medicare coverage because they have received Social Security Disability Insurance (SSDI) for 24 months or have specific conditions like End-Stage Renal Disease or Amyotrophic Lateral Sclerosis (ALS). It helps healthcare providers and insurers identify the reason for a person's Medicare eligibility.