Part B premiums increased to $202.90 in 2026, which is a 9.7% increase from the $185 that premiums cost in 2025. Orman specifically warned Social Security retirees about this because the big increase in Medicare insurance costs in 2026 would mean that the Cost of Living Adjustment (COLA) applied to seniors' retirement checks this year would be substantially reduced by the added premiums they now have to pay.