Individual Insurance

Prescription Drug Coverage During 2027 Open Enrollment: How Formularies Affect Your Choice

By Paul Z Olah  |  October 8, 2026

For people who take regular medications, prescription drug coverage is one of the most important factors in choosing a health insurance plan during 2027 Open Enrollment. Getting this wrong can cost you thousands of dollars. Here’s how to evaluate drug coverage the right way.

What Is a Formulary?

A formulary is an insurance plan’s list of covered prescription drugs. Every marketplace plan has its own formulary — and they vary significantly. A drug that’s a cheap generic on one plan may be a high-cost Tier 3 brand drug on another.

Formularies are organized into cost tiers:

  • Tier 1 (Generic): Lowest copay, often $0–$10 per fill
  • Tier 2 (Preferred Brand): Moderate copay, typically $30–$60
  • Tier 3 (Non-Preferred Brand): Higher copay, often $60–$100+
  • Tier 4 (Specialty): Highest cost, often 20–40% coinsurance after deductible

How to Check a Plan’s Formulary

Every marketplace plan is required to make its formulary publicly available. When comparing plans:

  1. Make a list of every prescription taken by anyone who will be on the plan (name, dosage, frequency)
  2. For each plan you’re considering, search the formulary online (usually at the insurer’s website)
  3. Note the tier each drug is on and the associated cost
  4. Check whether any drugs require prior authorization or step therapy
  5. Confirm the plan uses pharmacies convenient to you

Prior Authorization and Step Therapy

Some plans require prior authorization for certain drugs — meaning you need pre-approval from the insurer before the drug is covered. Others require step therapy — you must try a cheaper drug first before the preferred drug is approved. If you’re on a specific medication for a chronic condition, confirm whether these requirements apply and factor in the administrative burden.

Specialty Medications

For specialty drugs (biologics, cancer treatments, rare disease therapies), formulary placement and cost-sharing can be dramatic. Plans often apply high coinsurance rates rather than flat copays for specialty drugs — 30% coinsurance on a $15,000/month medication means $4,500/month out of pocket until you hit your OOPM. For high-cost specialty meds, look for plans with:

  • Low out-of-pocket maximums
  • Favorable specialty drug tier placement
  • Manufacturer copay assistance compatibility (some plans specifically block this)

Mail-Order Pharmacies

Many plans offer significant discounts for 90-day mail-order fills of maintenance medications vs. retail pharmacy 30-day fills. If you take daily chronic medications, confirm whether the plan has a preferred mail-order pharmacy and what the savings are.

Taking regular medications and want to verify they’re covered before choosing a 2027 plan? Contact Paul at Garden State Benefits for a no-cost, no-obligation review of your 2027 options — he’s a licensed independent broker serving individuals and families across 26 states.

Schedule Your Free 2027 Open Enrollment Consultation

Pick a time that works for you — Paul will walk you through your options, compare plans, and answer every question.

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