How this calculator works
Coverage year: 2026, United States. The standard Part B premium is $202.90 a month and the annual deductible is $283 per person. Part B starts in the month of enrolment, so a person who enrols in July pays six months of premium in calendar 2026 rather than twelve. The deductible is counted once per person for the year, whatever the enrolment month. The model covers calendar 2026 only: it does not project later years, when CMS sets a new premium and deductible. It also leaves out income-related monthly adjustment amounts, which are on the IRMAA page, the Part A premium, Part D and Medicare Advantage premiums, late enrolment penalties, the seven-month initial enrolment period and any help from a State Pharmaceutical Assistance Program or Medicaid.
Formula
Months charged = 13 - enrolment month number. Annual premium = $202.90 x months charged x people enrolled. Annual deductible = $283 x people enrolled. Calendar-year cost = annual premium + annual deductible.
Worked example
One person enrols in July 2026. Six months are charged, so the premium is 6 x $202.90, which is $1,217.40. The deductible is $283, so the calendar-year cost is $1,500.40. A second person enrolling in the same month doubles both amounts.
Frequently asked questions
What is the Medicare Part B premium for 2026?
The standard premium is $202.90 a month, an increase of $17.90 from $185.00 in 2025. People above the income thresholds pay an income-related adjustment on top.
What is the Part B deductible in 2026?
The annual deductible is $283 per person, up $26 from $257 in 2025. It applies once per person for the year.
When do Part B premiums start?
Premiums start in the month your coverage begins, not the month you apply. Enrolling later in the year therefore means fewer months of premium in that calendar year.
Does this include the IRMAA surcharge?
No. Higher-income beneficiaries pay an income-related monthly adjustment amount, which depends on modified adjusted gross income from two years earlier. The Medicare IRMAA page models that separately.