How to choose a health insurance plan and avoid big bills

Open enrollment is your yearly chance to head off big medical bills before they start. The plan with the lowest monthly price isn't always the cheapest one over a full year. And a plan that leaves out your doctor can cost you far more than it saves.

This guide shows how to choose a health insurance plan by comparing what you'd really pay. It's part of our guide on how to avoid surprise medical bills. We can't tell you which plan is right for you, but we can show you how to compare them.

What do premiums, deductibles and out-of-pocket maximums mean?

Every plan has a few costs that work together. Here's what each one means:

The out-of-pocket maximum is your safety net. Once your deductible, copays and coinsurance reach it, your plan pays 100% of covered in-network care for the rest of the year.

But it doesn't cover everything. Premiums don't count toward it. Neither do services your plan doesn't cover, or out-of-network care. That's why networks matter so much, as Steps 3 and 4 explain.

For 2027, a Marketplace plan's out-of-pocket maximum can't be more than $12,000 for 1 person or $24,000 for a family. A plan can set a lower one.

Step 1: Estimate how much care you'll use

Start with the year behind you. Look at last year's claims in your insurer's app, or your explanation of benefits (EOB) statements. Add up roughly what you paid for care.

Then think about the year ahead. Write down:

• Regular visits, like checkups, therapy or specialist care
• Prescriptions you take every month
• Planned care, like a surgery, a scan or having a baby
• Ongoing conditions that need tests or treatment

You can't predict everything, and that's fine. The goal is to sort your year into light, medium or heavy use.

Step 2: Add up the total yearly cost for each plan

For each plan, work out 2 numbers.

1. Your likely year: 12 months of premiums plus what you'd pay for the care you expect.
2. Your worst year: 12 months of premiums plus the out-of-pocket maximum.

The first tells you which plan likely costs less. The second tells you how much you'd owe if something big and unplanned happened.

Deductibles, copays and coinsurance can add up to more than a plan's premiums. So a plan that looks cheap each month can turn out to be the costly one.

Say Maya can choose between 2 plans at work. To keep the math simple, assume all her care is covered, in-network, and counts toward the deductible.

	Plan A	Plan B
Monthly premium	$250	$450
Premiums for the year	$3,000	$5,400
Deductible	$5,000	$1,000
Coinsurance after the deductible	20%	20%
Out-of-pocket maximum	$8,000	$4,000

Here's what she'd pay in a year, premiums included, at 3 levels of care.

Covered care in the year	Plan A total	Plan B total
$1,000	$4,000	$6,400
$4,000	$7,000	$7,000
$20,000	$11,000	$9,400

Here's the math for the $20,000 year.

• Plan A: $5,000 deductible + 20% of the other $15,000 ($3,000) = $8,000. That's exactly the out-of-pocket maximum. With $3,000 in premiums, her total is $11,000.
• Plan B: $1,000 deductible + 20% of the other $19,000 ($3,800) = $4,800. That's over the $4,000 maximum, so she pays $4,000. With $5,400 in premiums, her total is $9,400.

In a light year, Plan A saves her $2,400. At $4,000 of care, the 2 plans cost the same. In a heavy year, Plan B saves her $1,600.

Maya's worst year matches the $20,000 row: $11,000 with Plan A, or $9,400 with Plan B. If Plan A is eligible for a health savings account, she could save toward its deductible there. That can lower her taxes, but it doesn't change the totals above.

Real plans have more moving parts. Some charge copays for visits or drugs before the deductible. If your employer puts money into a health savings account, subtract it from that plan's total.

On the Marketplace, your income may qualify you for extra savings on a Silver plan. With extra savings, a Silver plan pays a bigger share of your costs, so compare those plans closely.

Step 3: Pick a network type that fits how you get care

A plan's network is the group of doctors, hospitals and other providers it contracts with. The network type decides whether you can go outside it.

An HMO or EPO works best when all your doctors are in its network. A PPO gives you more choice, but care outside the network costs you more.

Out-of-network care is where many big bills come from. It usually doesn't count toward your out-of-pocket maximum. Out-of-network providers may also bill you for the gap between their price and what your plan pays. Federal law limits that in emergencies and some other cases, but not all.

Step 4: Check your doctors, hospitals and prescriptions

Before you pick, check each plan for the care you already use:

• Your primary care doctor and any specialists
• The hospital you'd want to use, and its emergency room
• Your pharmacy
• Each prescription, at the dose you take

Each plan posts a provider directory and a list of covered drugs, called a formulary. On HealthCare.gov, you can add your doctors, facilities and drugs while you compare plans. It then shows which plans cover them in-network.

Directories can be wrong, so confirm by phone. Call the doctor's office and ask if they take the exact plan name, not just the insurer. Save a screenshot and notes with the date. Our guide on how to check if a doctor is in network walks through each step and why the proof matters.

If you have planned care coming up, look at prices too. Our hospital price transparency lookup guide shows how to see what a hospital charges.

Step 5: Read each plan's summary of benefits and coverage

Health plans must give you a Summary of Benefits and Coverage (SBC). It uses the same format for every plan, so you can compare them side by side. You'll get one when you shop at work or on your own, and you can ask for one anytime. Plans must send it within 7 business days of a request.

Look for these parts:

• Important questions: the deductible, the out-of-pocket limit, the network, and whether you need referrals
• Common medical events: what you'd pay for a doctor visit, a test, a drug, outpatient surgery, emergency care or a hospital stay
• Excluded services: what the plan doesn't cover at all
• Coverage examples: what you might pay for having a baby, managing type 2 diabetes, or a simple fracture

The coverage examples are a quick way to compare plans for a bad year. Just remember they're examples, not quotes. The SBC also doesn't list premiums, so get those from the plan's price page or your employer.

Step 6: Decide whether an HSA-eligible plan fits

A health savings account (HSA) lets you set aside money for medical costs with tax advantages. Contributions can lower your taxable income. Money you take out for qualified medical expenses isn't taxed.

To put money into an HSA, you generally need to be in a high-deductible health plan. You also can't have other health coverage, with some exceptions, or be enrolled in Medicare. Since January 1, 2026, all Bronze and Catastrophic Marketplace plans count as HSA-eligible.

An HSA-eligible plan can make sense if you can afford its higher deductible in a bad year. Ask whether a plan is HSA-eligible, or use the "Eligible for an HSA" filter on HealthCare.gov. For using HSA money on bills you already have, see using an HSA for past medical bills.

Step 7: Enroll before the deadline

Dates depend on where your coverage comes from.

Marketplace plans (HealthCare.gov) for 2027:

• November 1, 2026: Open enrollment starts.
• December 15, 2026: Last day to enroll for coverage that starts January 1, 2027.
• January 15, 2027: Open enrollment ends. Plans you pick after December 15 start February 1, 2027.

If your state runs its own marketplace, check its website for its dates.

Job-based plans: Your employer sets its own open enrollment period. Watch for an email or packet from your benefits office, and ask for each plan's SBC.

Medicare: Open enrollment runs October 15 to December 7 each year. You can switch between Original Medicare and Medicare Advantage, or change your drug plan. Your new coverage starts January 1. If you're already in a Medicare Advantage plan, you get another chance from January 1 to March 31.

If this doesn't work

Sometimes the plan you picked doesn't work out. Here's what you can do:

• Your doctor leaves the network. Call your plan and ask about your options. Then use the directory to find an in-network replacement.
• Your life changes. Losing other coverage, getting married, having a baby or moving can open a special enrollment period. For Marketplace plans, you generally have 60 days. For job-based plans, you must ask within 30 days of a marriage, birth or adoption.
• You get a bill you didn't expect. Compare it with your EOB before you pay. Our guide to comparing a medical bill vs. EOB shows how.
• You're paying for care yourself. Ask for a written estimate first. Our guide to good faith estimates and the $400 dispute rule explains your rights.

Otherwise, you can switch plans at the next open enrollment.

When to get help

You can compare most plans yourself in about an hour. It's worth getting help when:

• You're choosing between plans with very different networks or drug lists.
• You or someone in your family has a serious or ongoing condition.
• You're helping a parent compare Medicare plans.
• You're not sure whether you qualify for lower costs based on income.

For Marketplace plans, call HealthCare.gov at 1-800-318-2596, or use its Find Local Help tool. For job-based plans, ask your employer's benefits office.

For Medicare, call 1-800-MEDICARE (1-800-633-4227). Your State Health Insurance Assistance Program (SHIP) also gives free counseling. Find yours at shiphelp.org.

Your state insurance department can answer questions about plans sold in your state. A medical bill advocate can help once bills arrive. If a bill is already more than you can pay, see what to do if you can't afford medical bills.