Rex says
Money math without the spreadsheet headache. Plug in your numbers and I'll show you exactly where the dollars land.
Try a scenario
Click to load — tweak from there.Inputs
Result
Total monthly Medicare cost
$225.00
Part B total (incl. IRMAA/penalty)
$185.00
Part D total (incl. IRMAA/penalty)
$40.00
Total annual Medicare cost
$2,700
Part B late penalty portion
$0.00
Part D late penalty portion
$0.00
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter standard part b premium ($).
- 2Enter part b irmaa surcharge ($).
- 3Enter full 12-month periods late enrolling part b.
- 4Enter part d plan premium ($).
- 5Enter part d irmaa surcharge ($).
- 6Enter months without creditable drug coverage.
- 7Enter medigap / medicare advantage premium ($).
- 8Read your total monthly medicare cost on the right — it updates as you type.
- 9Hit Share to keep the scenario or send it to someone.
About this calculator
Your all-in Medicare cost is more than the headline Part B number. It typically includes the standard Part B premium, any IRMAA surcharge, your chosen Part D drug plan premium, possible IRMAA on Part D, a late-enrollment penalty if you signed up after your initial enrollment window without other creditable coverage, and often a Medigap or Medicare Advantage premium on top. Late enrollment penalties compound over time: Part B adds 10% of the standard premium for each full 12-month period you delayed, permanently, while Part D adds roughly 1% of the national base beneficiary premium per month you went without creditable drug coverage. This calculator totals everything into one realistic monthly and annual number so you're not surprised by the gap between the number quoted at sign-up and what actually hits your Social Security deduction or bill.
Worked example
Using the values the calculator loads with:
Inputs
- Standard Part B premium: 185 $
- Part B IRMAA surcharge: 0 $
- Full 12-month periods late enrolling Part B: 0
- Part D plan premium: 40 $
- Part D IRMAA surcharge: 0 $
- Months without creditable drug coverage: 0
- Medigap / Medicare Advantage premium: 0 $
Results
- Total monthly Medicare cost: $225.00
- Part B total (incl. IRMAA/penalty): $185.00
- Part D total (incl. IRMAA/penalty): $40.00
- Total annual Medicare cost: $2,700
- Part B late penalty portion: $0.00
- Part D late penalty portion: $0.00
What each field means
Inputs
- Standard Part B premium ($)
- The standard part b premium used in the calculation, measured in $. Starts at 185 $ so you have a working example on load.
- Part B IRMAA surcharge ($)
- The part b irmaa surcharge used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
- Full 12-month periods late enrolling Part B
- The full 12-month periods late enrolling part b used in the calculation. Starts at 0 so you have a working example on load. Accepted range: 0–10.
- Part D plan premium ($)
- The part d plan premium used in the calculation, measured in $. Starts at 40 $ so you have a working example on load.
- Part D IRMAA surcharge ($)
- The part d irmaa surcharge used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
- Months without creditable drug coverage
- The months without creditable drug coverage used in the calculation. Starts at 0 so you have a working example on load. Accepted range: 0–240.
- Medigap / Medicare Advantage premium ($)
- The medigap / medicare advantage premium used in the calculation, measured in $. Starts at 0 $ so you have a working example on load.
Results
- Total monthly Medicare cost
- Returned as a money amount in US dollars and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Part B total (incl. IRMAA/penalty)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Part D total (incl. IRMAA/penalty)
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Total annual Medicare cost
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Part B late penalty portion
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Part D late penalty portion
- Returned as a money amount in US dollars. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
Is the Part B late penalty temporary?
No, it's permanent for as long as you have Part B. Unlike Part D, there's no expiration — a 20% permanent surcharge (from two years of delay) stays on your premium for life, which is why enrolling during your initial enrollment period or a valid special enrollment period matters so much.
How is the Part D penalty calculated exactly?
SSA multiplies 1% of that year's national base beneficiary premium by the number of full months you went without Part D or other creditable prescription coverage after your initial enrollment period ended, then rounds to the nearest 10 cents. The national base premium changes annually, so the penalty dollar amount can shift slightly each year even though the percentage stays fixed.
Do I need Part D if I don't take prescriptions now?
Most people should still enroll or maintain creditable employer coverage, because the penalty is based on any gap, not current need, and health changes unpredictably. Skipping it to save a small monthly premium can cost far more in permanent penalties once you do need drug coverage.
What's the difference between Medigap and Medicare Advantage cost-wise?
Medigap charges its own separate premium on top of Original Medicare and Part D but covers most out-of-pocket costs Original Medicare leaves behind. Medicare Advantage often has lower or $0 premiums but bundles different cost-sharing, networks, and caps — comparing them requires looking at total expected annual cost, not just the premium line.
Accuracy and limitations
- Results are estimates before tax, fees, and inflation unless an input explicitly covers them.
- Rates are treated as fixed for the whole period — variable-rate products will drift from this projection.
- This is educational maths, not financial advice. Check anything contractual with the lender or your accountant.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). Medicare Part B/D Premium Total Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/medicare-premium-total
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/medicare-premium-total" target="_blank" rel="noopener">Medicare Part B/D Premium Total Calculator — RevenueLab</a> (2026).</p>
Source: [Medicare Part B/D Premium Total Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/medicare-premium-total) (2026).