A COBRA cost calculator estimates what you will pay each month to keep your employer health plan after leaving a job. The COBRA cost calculator uses this formula: Base = monthly premium, or W-2 Box 12 DD ÷ 12. Monthly COBRA = base × (1 + adminFeePct/100). Total = monthly × months. COBRA can cost up to 102% of the full premium, including the share your employer used to pay. A plan that costs $650 a month in total would cost about $663 a month under COBRA, or $11,934 for 18 months.
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How to use the COBRA cost calculator
- Enter the full monthly premium (employee plus employer), or choose the W-2 method and enter Box 12 code DD.
- Enter the number of months you expect to use COBRA.
- Read the monthly COBRA premium, the 2% fee and the total.
What formula does the COBRA cost calculator use?
- Monthly COBRA premium = full group premium × 1.02
- Full group premium = what you and your employer together pay each month, or W-2 Box 12 code DD ÷ 12
- Total cost = monthly COBRA premium × months of coverage
Federal COBRA rules let plans charge up to 102% of the plan’s cost: the full premium plus a 2% administrative fee. During a disability extension, the charge can rise to 150% for the extra months.
COBRA cost calculator worked example
| Full monthly premium | COBRA monthly (102%) | 18 months |
|---|---|---|
| $650.00 | $663.00 | $11,934.00 |
| $1,200.00 | $1,224.00 | $22,032.00 |
| $1,800.00 | $1,836.00 | $33,048.00 |
| $2,000.00 | $2,040.00 | $36,720.00 |
If your W-2 Box 12 code DD shows $24,000 for the year, the full premium is about $2,000 a month and COBRA would be about $2,040. Box DD includes both your share and your employer’s share of the cost of coverage.
COBRA basics
- Federal COBRA generally applies to group health plans of employers with 20 or more employees; many states have “mini-COBRA” laws for smaller employers.
- Coverage usually lasts up to 18 months after job loss or reduced hours, and up to 36 months for some events such as divorce or a dependent child aging out.
- You have at least 60 days to elect COBRA, and coverage is retroactive to the date you lost coverage once you elect and pay.
- You keep the same plan, network and deductible progress.
- After you elect, the plan must give you at least 45 days to make the first premium payment; later payments generally have a 30-day grace period.
COBRA vs a Marketplace plan
Losing job-based coverage qualifies you for a special enrollment period on HealthCare.gov or your state Marketplace, generally 60 days. Depending on your income, a Marketplace plan with premium tax credits may cost much less than COBRA. If you are mid-treatment or have met your deductible, COBRA can still be worth it for a few months. Compare the monthly cost, deductible and network before you decide.
Budgeting for COBRA
Ask your former employer for the COBRA election notice, which shows the exact premium. Check whether a severance package includes help with COBRA premiums, and whether a spouse’s plan would accept you. The COBRA cost calculator uses one premium for every month, but plan rates often change at the start of a new plan year, so redo the estimate then. Coverage can also end early if you stop paying or gain other group coverage.
Estimates for education only, not financial advice. Your lender’s figures are final.
Worked example: family coverage
COBRA lets a plan charge up to 102% of the full cost of coverage, the share your employer paid plus your share. Suppose family coverage costs $1,800 a month in total and the employee paid $450 while working. Under COBRA the premium can be $1,836, so the monthly cost rises by $1,386. Over the usual 18 months that is $33,048. If a disabled family member qualifies for the 11-month extension, the plan can charge up to 150% for those months.
You have 60 days to elect COBRA and 45 days after electing to make the first payment, and coverage is retroactive once you pay. That gap lets you compare options before committing. Enter the full plan cost in the COBRA cost calculator, then compare the result with a Marketplace quote that reflects any premium tax credit you qualify for. The COBRA cost calculator answer is often the more expensive one.
Related converters and calculators
Related calculators:
- Severance pay calculator: severance
- Final paycheck calculator: last check
- PTO payout calculator: unused leave
Sources
U.S. DOL: Continuation of Health Coverage (COBRA); HealthCare.gov: COBRA coverage and the Marketplace.
Questions about this calculator
How much does COBRA cost?
Up to 102% of the full premium for your coverage, including your former employer’s share.
How long does COBRA last?
Usually 18 months, and up to 36 months for certain qualifying events.
How long do I have to elect COBRA?
At least 60 days from the later of losing coverage or receiving the election notice.
Can I find my premium on my W-2?
Box 12 code DD shows the yearly cost of coverage; divide by 12 for a monthly estimate.
Is a Marketplace plan cheaper than COBRA?
Often, if you qualify for premium tax credits. Compare both.
Check the assumptions and units before relying on a result. Financial, tax and health estimates do not replace advice for your individual circumstances.
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