Health Insurance Basics: Deductibles, Copays, and How to Choose a Plan
Health insurance terminology is deliberately confusing. Deductibles, copays, coinsurance, out-of-pocket maximums, HMOs, PPOs, EPOs, HDHPs — the alphabet soup of health insurance discourages comparison shopping, which is exactly what insurers want. When you do not understand what you are buying, you default to the cheapest premium or the plan your employer recommends, neither of which may be the best choice for your situation. This guide translates the jargon into plain language and gives you a framework for choosing the plan that actually matches your healthcare needs and budget.
The Four Key Cost Components
Every health insurance plan has four cost layers: premiums, deductibles, copays or coinsurance, and out-of-pocket maximums. Your premium is the monthly cost of having the plan. Your deductible is the amount you pay out of pocket before the insurance starts covering expenses. Copays are flat fees you pay per visit or service. Coinsurance is the percentage of costs you pay after meeting the deductible.
The out-of-pocket maximum is the most important number: it is the absolute ceiling on what you pay in a year, after which the insurer covers 100 percent. For 2025, the ACA maximum is $9,200 for an individual and $18,400 for a family. Once you hit this limit, every additional medical expense that year is fully covered. Plans with lower out-of-pocket maximums provide more protection against catastrophic costs but typically charge higher premiums.
Plan Types: HMO, PPO, EPO, and HDHP
An HMO requires you to choose a primary care physician who coordinates all your care and issues referrals to specialists. You must use in-network providers except in emergencies. HMOs have the lowest premiums and copays but the least flexibility. A PPO lets you see any provider — in-network or out — without referrals, but out-of-network care costs significantly more. PPOs have higher premiums but maximum flexibility.
An EPO is a hybrid: no referrals needed, but you must stay in-network (no out-of-network coverage at all). An HDHP is a high-deductible health plan paired with a Health Savings Account. You pay a high deductible ($1,600 to $3,200 for individuals in 2025) before insurance kicks in, but premiums are low and the HSA provides triple tax advantages — tax-deductible contributions, tax-free growth, and tax-free withdrawals for medical expenses.
- HMO: lowest premiums, requires referrals, in-network only
- PPO: higher premiums, no referrals, in-network and out-of-network
- EPO: moderate premiums, no referrals, in-network only
- HDHP: lowest premiums, high deductible, paired with HSA for tax savings
How to Choose the Right Plan
Start with your actual healthcare usage. Pull your Explanation of Benefits statements from the past year and add up what you paid in premiums, deductibles, copays, and coinsurance. This is your baseline cost. Then model the same year under each available plan. The plan with the lowest total cost for your actual usage pattern is usually the best choice.
Consider worst-case scenarios too. If you were hospitalized for two weeks, what would each plan cost? The out-of-pocket maximum answers this question. A plan with a $2,000 premium difference but a $4,000 lower out-of-pocket maximum protects you better against catastrophic events while costing only slightly more in the best-case scenario.
Common Health Insurance Mistakes
Choosing the cheapest premium without examining the deductible and out-of-pocket maximum is the most expensive mistake. A plan saving $100 per month in premiums but adding $3,000 to the deductible costs more if you have any significant medical expense. Always compare total potential costs, not just premiums.
Failing to verify that your doctors and medications are in-network before enrolling catches thousands of people every year. Switching plans can mean losing access to your current providers. Check the plan's provider directory and formulary before enrollment, not after. Also ensure your preferred hospital and any specialists you see regularly are included.
Frequently Asked Questions
What is the difference between a copay and coinsurance?
A copay is a flat fee you pay per visit or service — for example, $30 for a doctor visit or $15 for a prescription. Coinsurance is a percentage of the cost you pay after meeting your deductible — for example, 20 percent of a $10,000 surgery means you pay $2,000. Copays are predictable; coinsurance varies with the cost of the service.
Is an HDHP better than a PPO?
It depends on your healthcare usage. An HDHP with an HSA is typically better for healthy individuals with low annual healthcare costs — the premium savings and tax benefits of the HSA outweigh the higher deductible. A PPO is typically better for people with chronic conditions, families with frequent specialist visits, or anyone who expects significant healthcare expenses.
What happens if I go out of network with an HMO?
In most cases, the HMO pays nothing for out-of-network care except in genuine emergencies. You would be responsible for 100 percent of the cost. This is the biggest drawback of HMO plans and why verifying network coverage before receiving care is essential.
Can I change my health insurance plan outside of open enrollment?
Only with a qualifying life event: marriage, divorce, birth or adoption of a child, loss of other coverage, moving to a new area, or significant change in income. These events trigger a Special Enrollment Period, typically 30 to 60 days, during which you can change plans. Without a qualifying event, you must wait for the annual open enrollment period.
What is an HSA and why does it matter?
A Health Savings Account is a tax-advantaged account available to people with HDHPs. Contributions are tax-deductible, growth is tax-free, and withdrawals for qualified medical expenses are tax-free — triple tax savings that no other account type offers. In 2025, you can contribute up to $4,300 individually or $8,550 for families. Unused funds roll over indefinitely and after age 65 can be used for any purpose.