How Health Insurance Works
Health insurance is a financial arrangement where members pay premiums in exchange for the insurer covering a portion of their healthcare costs. Understanding how cost-sharing, networks, and managed care models work is essential for anyone in the healthcare ecosystem.
Cost-Sharing Components
| Component | Definition |
|---|---|
| Premium | Monthly payment to maintain coverage (whether or not you use services) |
| Deductible | Amount you pay out-of-pocket before the plan starts paying (e.g., $1,500/year) |
| Copay | Fixed dollar amount per service (e.g., $25 for a PCP visit, $50 for a specialist) |
| Coinsurance | Percentage you pay after meeting the deductible (e.g., 20% of allowed amount) |
| Out-of-Pocket Maximum | The most you pay in a year; after this, the plan pays 100% (ACA max: ~$9,450 individual / ~$18,900 family) |
How Cost-Sharing Works in Practice
- Member pays full cost up to the deductible (preventive services are excluded under ACA — covered at 100%)
- After deductible, member pays coinsurance (e.g., 20%) on each service
- Once total out-of-pocket costs reach the OOP maximum, the plan covers 100%
In-Network vs. Out-of-Network
- In-network providers have contracted rates with the insurer — resulting in lower costs for the member
- Out-of-network providers have no contract — the member pays more (higher coinsurance, balance billing possible)
- Some plans (HMOs, EPOs) do not cover out-of-network care except in emergencies
Managed Care Models
| Model | Full Name | Referral Required? | Out-of-Network Coverage | Key Feature |
|---|---|---|---|---|
| HMO | Health Maintenance Organization | Yes | No (except emergencies) | Lowest premiums; must use network; PCP gatekeeper |
| PPO | Preferred Provider Organization | No | Yes (at higher cost) | Most flexibility; higher premiums |
| POS | Point of Service | Yes for specialists | Yes (at higher cost) | Hybrid of HMO and PPO |
| EPO | Exclusive Provider Organization | No | No (except emergencies) | Like PPO but no out-of-network coverage |
Choosing a Model
- HMO: Best for cost-conscious members who don't mind referrals and staying in-network
- PPO: Best for members who want flexibility to see any provider without referrals
- POS: Best for members who want a PCP but occasional out-of-network access
- EPO: Best for members who want no-referral access but are comfortable staying in-network
Prior Authorization
Many plans require prior authorization (pre-approval) before covering certain services:
- Elective surgeries
- Advanced imaging (MRI, CT, PET)
- Specialty medications (biologics, gene therapies)
- Inpatient admissions
- Certain DME (durable medical equipment)
The provider submits a request (historically via EDI 278 or phone/fax; increasingly via FHIR-based APIs under CMS mandates). The payer reviews medical necessity and approves, denies, or pends the request.
Prescription Drug Coverage
Most health plans include pharmacy benefits with tiered formularies:
| Tier | Drug Type | Typical Copay |
|---|---|---|
| Tier 1 | Preferred generics | $5-15 |
| Tier 2 | Non-preferred generics | $15-30 |
| Tier 3 | Preferred brand | $30-60 |
| Tier 4 | Non-preferred brand | $60-100 |
| Tier 5 | Specialty medications | 20-33% coinsurance |
Pharmacy Benefit Managers (PBMs) — such as Express Scripts, CVS Caremark, and OptumRx — negotiate drug prices, manage formularies, and process pharmacy claims on behalf of health plans.
