Stop Guessing at Open Enrollment — Run the Math Instead
Every fall, millions of people stare at a benefits portal comparing health insurance options and make their choice based on gut feel. The premium looks lower, so they pick the high-deductible plan. Or the deductible looks scary, so they stick with the PPO they've always had. Neither approach is wrong by instinct alone, but both leave real money on the table when you haven't done the actual calculation.
Health insurance plan selection is a break-even problem. You're trying to find the point at which Plan A stops being cheaper than Plan B, and then estimate which side of that line your actual life is likely to land on. It's not complicated math, but it requires you to pull three or four numbers together in a way most people never do.
This article walks you through that entire process — from premium comparison to worst-case scenario analysis to HSA tax savings — so you can make an evidence-based decision during open enrollment instead of a hopeful one.
The Four Numbers That Actually Matter
Before you can run a break-even analysis, you need to understand what each cost component actually represents and how they interact. Skipping this step is why most plan comparisons fall apart.
Monthly Premium
This is what you pay to have coverage, regardless of whether you use a single dollar of care. Your employer likely covers a portion — sometimes a large one. What matters for your comparison is your out-of-pocket premium, after the employer subsidy. If your employer pays $600/month toward a PPO and you pay $180, your premium cost is $180/month, not the full $780 plan cost.
Deductible
This is what you pay before your insurance starts covering a significant share of your costs. A $1,500 deductible means you pay the first $1,500 of covered medical expenses each year. Note: premiums, dental, and vision often don't count toward your medical deductible. Prescriptions may or may not, depending on your plan.
Coinsurance and Copays
After your deductible, most plans require you to keep paying a percentage of costs (coinsurance) or a flat fee per visit (copay). A plan with 20% coinsurance means you pay 20 cents of every dollar in medical bills until you hit the out-of-pocket maximum. Some plans have copays instead — a flat $30 per primary care visit, $50 per specialist — which kick in immediately without needing to meet the deductible first.
Out-of-Pocket Maximum
This is your absolute ceiling. Once your deductible plus coinsurance payments reach this number, insurance covers 100% for the rest of the year. In 2024, the federal limit for out-of-pocket maximums is $9,450 for individual coverage and $18,900 for families. This number is your worst-case scenario, and it's the most important figure in a catastrophic year.
The Break-Even Formula
Here's the core calculation. You're comparing two plans — let's call them Plan A (lower premium, higher deductible) and Plan B (higher premium, lower deductible). The question is: at what level of annual medical spending does Plan B become worth the extra premium cost?
Break-Even Medical Spend = (Annual Premium Difference) ÷ (Cost-Sharing Difference Rate)
But in practice, it's cleaner to build a total annual cost model for each plan at three scenarios: low utilization, medium utilization, and high utilization. Here's how to do it.
Step 1: Calculate Your Annual Premium Cost
Take your monthly out-of-pocket premium and multiply by 12. Do this for each plan you're comparing.
Example: Plan A (HDHP) costs you $95/month = $1,140/year. Plan B (PPO) costs you $290/month = $3,480/year. The PPO costs $2,340 more per year before you've used a single service.
Step 2: Model Three Utilization Scenarios
You don't know exactly what care you'll need, but you can build three brackets:
- Low utilization: Healthy year — one or two primary care visits, maybe a prescription or two. Estimate $300–$600 in actual medical services.
- Medium utilization: Typical year with some care — a specialist visit, a minor procedure, ongoing prescriptions. Estimate $1,500–$4,000 in services.
- High utilization: A significant health event — surgery, ER visit, pregnancy, chronic condition management. Assume you hit or approach your out-of-pocket maximum.
Step 3: Calculate Total Out-of-Pocket for Each Scenario
For each plan, add the annual premium to what you'd actually pay in cost-sharing (deductible + coinsurance/copays) at each utilization level. Cap cost-sharing at the plan's out-of-pocket maximum.
Let's use a real worked example.
A Worked Example: HDHP vs. PPO
You're a 34-year-old choosing between two plans at open enrollment. Here are the numbers:
Plan A — HDHP: $95/month premium ($1,140/year), $1,600 individual deductible, 20% coinsurance after deductible, $5,000 out-of-pocket maximum. Your employer contributes $800/year to an HSA.
Plan B — PPO: $290/month premium ($3,480/year), $500 individual deductible, $30 primary care copay / $50 specialist copay, 20% coinsurance after deductible, $3,500 out-of-pocket maximum.
Scenario 1: Low Utilization ($600 in medical services)
HDHP: You pay $1,140 in premiums + $600 in medical costs (all under deductible) = $1,740 total. Subtract the $800 employer HSA contribution: effective cost = $940.
PPO: You pay $3,480 in premiums + two primary care visits at $30 each + one specialist at $50 = $3,480 + $110 = $3,590 total. (Most of the $600 in services is handled by copays.)
HDHP wins by $2,650. If you're young and healthy, this is a significant annual savings.
Scenario 2: Medium Utilization ($3,000 in medical services)
HDHP: $1,140 premiums + $1,600 deductible + 20% of remaining $1,400 = $1,140 + $1,600 + $280 = $3,020. Subtract $800 HSA employer contribution: effective cost = $2,220.
PPO: $3,480 premiums + $500 deductible + 20% of remaining $2,500 = $3,480 + $500 + $500 = $4,480 total.
HDHP still wins, by $2,260. The PPO's higher premium is doing you no favors here.
Scenario 3: High Utilization (hitting out-of-pocket maximum)
HDHP: $1,140 premiums + $5,000 out-of-pocket maximum = $6,140. Subtract $800 HSA employer contribution: effective cost = $5,340.
PPO: $3,480 premiums + $3,500 out-of-pocket maximum = $6,980 total.
Remarkably, the HDHP still wins in the worst-case scenario — by $1,640. This is a genuinely good HDHP offer. Many situations won't look this clean, which is exactly why you need to run the numbers rather than assume the PPO protects you better in a catastrophic year.
Use our Health Insurance Break-Even Calculator on unreliant.com to plug in your actual plan figures and generate this comparison automatically for your situation.
Where HSAs Change Everything
If you choose a qualifying High-Deductible Health Plan, you're eligible to open a Health Savings Account. This isn't just a savings account — it's the only triple-tax-advantaged account in the U.S. tax code, and most people underuse it dramatically.
The Triple Tax Advantage
Contributions go in pre-tax (or are deductible if you contribute directly). The money grows tax-free. Withdrawals for qualified medical expenses are tax-free. At age 65, you can withdraw for any reason and pay only ordinary income tax — making it function like a traditional IRA with a healthcare bonus before that age.
2024 HSA Contribution Limits
For 2024, you can contribute up to $4,150 for individual coverage or $8,300 for a family plan. If you're 55 or older, you can add another $1,000 catch-up contribution. These limits include any employer contributions — so if your employer puts in $800, you can contribute up to $3,350 more on your own (individual limit).
The Real Tax Savings Calculation
Say you're in the 22% federal tax bracket and your state has a 5% income tax. Every dollar you contribute to your HSA saves you 27 cents in taxes (plus you avoid the 7.65% FICA tax on payroll contributions through your employer's cafeteria plan, bringing total savings closer to 35 cents per dollar for many employees).
If you contribute the full $4,150 individually and you're in that combined bracket, you're saving roughly $1,450 in taxes. That's not hypothetical — it's money you keep instead of sending to the IRS. Add that to your HDHP premium savings, and the math often becomes overwhelming in favor of the high-deductible plan for healthy individuals.
You can model this precisely with our HSA Tax Savings Calculator on unreliant.com, which factors in your federal bracket, state tax rate, and FICA treatment based on how you contribute.
The Strategic HSA Move Most People Miss
If you can afford to pay current medical expenses out of pocket, invest your HSA funds aggressively and let them grow for decades. Save your receipts — there's no time limit on HSA reimbursements. A receipt from 2024 can be reimbursed tax-free in 2039, after 15 years of tax-free compounding growth. This turns your HSA into a legitimate retirement healthcare reserve, and healthcare costs in retirement are among the largest financial risks most households face.
Adjusting for Your Actual Health Profile
The break-even model only works if your utilization estimate is realistic. Here's how to sharpen that number based on your actual situation.
Review Last Year's Explanation of Benefits
Your insurance company sends an Explanation of Benefits (EOB) for every claim. Log into your insurer's portal and look at your total billed charges and your actual paid amounts for the past 12 months. This is your most accurate utilization data. If you don't have last year's figures, use your best estimate of how many times you actually used care.
Planned Medical Events
If you know you're expecting a baby, scheduling surgery, starting a new medication, or managing a chronic condition, these are not uncertainty — they're known costs you can estimate. A vaginal delivery in the U.S. averages $13,000–$14,000 in total billed charges. With a $5,000 out-of-pocket maximum, you know you're hitting the cap regardless of plan. In that case, the entire comparison shifts to: which plan has the lower combined premium plus out-of-pocket maximum?
Ongoing Prescription Costs
Prescriptions are often the sleeper cost that breaks an HDHP analysis. Under a traditional PPO, you might pay $15–$40 per branded prescription with a copay. Under an HDHP, you pay the full negotiated rate until you hit your deductible — which can be $200–$400/month for some specialty medications. If you take maintenance medications, look up their plan-specific costs on the formulary, not just the deductible.
The Mental Health and Preventive Care Consideration
Under the ACA, preventive care — annual physicals, screenings, vaccines — must be covered at 100% with no cost-sharing under all plans, including HDHPs. You will not pay toward your deductible for a covered preventive visit. Mental health visits, however, are not preventive and typically count toward your deductible under an HDHP. If you see a therapist weekly at $150/session, that's $7,800/year in services — almost certainly pushing you toward your out-of-pocket maximum and making the PPO's copay structure look a lot more attractive.
Family Coverage: The Math Gets More Complex
Family plans have two sets of deductibles and out-of-pocket maximums: an individual limit and a family aggregate limit. Understanding how they interact is critical.
Embedded vs. Aggregate Deductibles
An embedded deductible means each family member has their own individual deductible, and no single person has to meet the full family deductible before their insurance kicks in. A $3,000 individual / $6,000 family embedded deductible means your child's costs trigger cost-sharing after $3,000, not after $6,000.
An aggregate deductible means the family must collectively meet the full deductible before anyone gets cost-sharing. A $6,000 aggregate family deductible means if only one person is sick, they pay $6,000 before insurance contributes — even if the plan shows a lower individual number. Many HDHPs use aggregate deductibles. Read the plan documents, not just the summary.
Family HDHP Minimum Deductible Requirements
For 2024, an HDHP must have a minimum deductible of $1,600 for individual coverage or $3,200 for family coverage to qualify for HSA contributions. If your plan's family deductible falls below $3,200, it may not qualify as an HDHP and you cannot contribute to an HSA — a fact that can significantly alter the family plan comparison.
Employer Contributions: The Variable Most People Ignore
Your employer's contribution to your premium isn't just a benefit — it's a differential that can completely change the comparison. Employers often contribute different dollar amounts to different plan tiers, and those differences are rarely obvious on benefits enrollment pages.
Ask your HR department for the total employer contribution toward each plan option. Sometimes the HDHP carries a larger employer premium subsidy — a deliberate incentive to steer employees toward cost-conscious plans. Other times, the contributions are equal regardless of plan. The difference matters because a $100/month larger employer contribution toward the HDHP is worth $1,200/year on top of any HSA seeding.
Some employers also contribute directly to your HSA as part of the HDHP package. This employer HSA contribution is not subject to payroll tax on either end — it's genuinely free money that belongs to you immediately or after a vesting period. If your employer puts $1,000 into your HSA when you enroll in the HDHP, that's equivalent to receiving a $1,000 raise for that choice.
Building Your Decision Matrix
Here's the practical framework to apply during your next open enrollment window:
- Pull your actual premium costs for each plan option after employer subsidy — not the plan's full premium, your cost.
- Note the deductible, coinsurance, copay structure, and out-of-pocket maximum for each plan.
- Identify any employer HSA contribution attached to HDHP options.
- Estimate your likely annual medical utilization using last year's EOBs or your best realistic assessment. Be honest — optimism bias is expensive.
- Calculate total annual cost for each plan at low, medium, and high utilization using the formula: Annual Premium + MIN(Actual Medical Costs Under Plan Rules, Out-of-Pocket Maximum).
- Subtract HSA tax savings from the HDHP total if applicable, based on your marginal tax rate.
- Compare the results across all three scenarios and see which plan wins consistently, or identify the crossover point.
- Account for planned events — known surgeries, pregnancies, or high prescription costs shift the analysis toward the scenario where they land.
If the HDHP wins in low and medium scenarios but the PPO wins in the high-utilization scenario, ask yourself: what's the realistic probability I hit that high scenario? For a 28-year-old with no chronic conditions, it might be 3–5%. For a 45-year-old managing hypertension and diabetes, it might be 30–40%. Probability-weight the outcomes accordingly.
When the PPO Is Actually the Right Answer
The math doesn't always favor the HDHP. The PPO wins when:
- The premium difference between plans is small (under $500/year) and your deductible difference is large
- You have high, predictable medical utilization that will regularly push you toward out-of-pocket maximums
- You take expensive maintenance medications that cost significantly more at full price under an HDHP
- Your PPO's out-of-pocket maximum is dramatically lower than the HDHP's, and you have reason to expect a high-cost year
- You have children with unpredictable health needs that make the aggregate deductible genuinely dangerous
- You cannot cash-flow the HDHP's higher upfront costs in a bad year, even if the math works out over the full year
That last point is underrated. A plan that technically saves you money but requires you to put $3,000 on a credit card in January until you hit your deductible isn't actually saving you money if you're paying 24% interest to carry that balance. Your cash flow matters as much as the annual total.
Run the Numbers Every Year
Your health changes. Your family changes. Employers adjust their plan contributions and options annually. A calculation you did three years ago may produce completely different results today with updated numbers. Open enrollment is not a set-and-forget decision — it's an annual math problem with real financial consequences.
If your employer offers a total of three or four plan options, you should be running this comparison for each pair. It takes less than an hour with the right tools. Our Health Insurance Comparison Calculator on unreliant.com lets you input all your plan parameters and generates the full break-even analysis side-by-side, including HSA tax savings and worst-case scenario totals, so you're not building spreadsheets from scratch every November.
The people who consistently pay less for healthcare aren't the ones who pick the plan with the lowest premium or the lowest deductible. They're the ones who actually read the plan documents, run the math for their specific situation, and choose accordingly. That's the entire advantage — and it's available to anyone willing to spend an hour on it.