Open enrollment · using last year's EOBs
Auto-renew, or switch?
Open enrollment asks you to forecast a year of health care you have not had yet. Your explanation-of- benefits statements already say what you used last year, at negotiated rates. Add up the allowed amounts, put both plan designs against that number, and the guesswork narrows to one question.
Runs in your browser. An arithmetic comparison, not enrollment advice — networks, formularies and prior-authorization rules can outweigh every number below.
Sum the allowed / negotiated amounts from your EOBs — not billed charges.
2026 limits: $4,400 self-only, $8,750 family, +$1,000 at 55+.
Federal + FICA + state, for the HSA tax benefit.
Plan A
What comes out of your paycheck, not the total cost.
Plan B · HSA-eligible
What comes out of your paycheck, not the total cost.
Any seed money the employer puts in.
At $6,800 of allowed charges
Total annual cost to you, premium plus cost sharing.
| Plan | Premiums | Cost sharing | HSA offset | Net cost |
|---|---|---|---|---|
| Current plan (auto-renew) | $2,520 | $2,560 | — | $5,080 |
| High-deductible + HSA | $1,140 | $4,160 | −$1,650 | $3,650 |
High-deductible + HSA comes out $1,430 ahead for the year at this level of care.
One plan wins at every level of care modelled here
Across the range modelled, High-deductible + HSA stays ahead. That usually means the premium gap is wide enough that cost sharing cannot close it — worth double-checking the premium figures before acting on it.
What this model leaves out
- Networks and formularies. A cheaper plan that drops your specialist or your drug tier is not cheaper.
- Separate prescription accumulators. Many plans run drug costs through their own deductible and copay structure rather than the medical one.
- The HSA as an investment. Money you do not spend stays yours, grows untaxed, and comes out untaxed for medical costs — often the biggest advantage of a high-deductible plan in a healthy year, and not counted above.
- Premium tax credits on marketplace coverage, which change the premium side entirely.
- An FSA you already have. A general-purpose health FSA balance carrying into next year blocks HSA contributions — check that before you elect a high-deductible plan.
Questions people ask about this
Which number from an EOB do I use?
The allowed amount, sometimes called the negotiated or contracted rate — not the billed charge and not what you paid. The allowed amount is what the plan and provider agreed the care is worth, and it is the figure every plan design applies its deductible and coinsurance to. Billed charges are frequently several times higher and will badly distort this comparison.
Why does last year predict next year at all?
Imperfectly, which is why the break-even matters more than the point estimate. Chronic conditions, ongoing prescriptions and routine care do repeat year to year. One-time events — a surgery, a birth, an injury — do not. If most of your spend was a one-time event, model a lower number and see whether the answer changes.
What is the break-even and why does it matter?
It is the level of allowed charges at which the two plans cost you the same. Below it the lower-premium plan wins; above it the richer plan does. It turns an uncertain forecast into a single question: is next year likely to be above or below that number? That is much easier to answer honestly than guessing a dollar total.
Does this account for the HSA?
Yes, in two ways. Any employer seed money is subtracted from the high-deductible plan cost, and the tax you avoid by routing your own contribution through payroll is subtracted too. The 2026 HSA limits are $4,400 self-only and $8,750 family, plus $1,000 if you are 55 or older. It does not model the long-term investment value of an HSA, which for a healthy year is often the largest benefit of all.
Is this enrollment advice?
No. This is an arithmetic comparison of two plan designs against a utilization figure you supply, and it deliberately ignores networks, formularies, prior authorization, out-of-network exposure and premium tax credits — any one of which can outweigh the arithmetic. Use it to narrow the question, then confirm with your benefits administrator or a licensed broker before you enroll.
Adding up a year of EOBs by hand?
Upload your explanation-of-benefits statements and get billed charges, allowed amounts, plan paid and patient responsibility back as structured data — then total the allowed column and drop it in above. Three free, no credit card.
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