Last verified: October 30, 2026, against OPM’s 2027 premium tables and the 2027 plan brochures linked below. Written by Casey Steward.
Every Open Season, a lot of people sort FEHB plans by premium, pick the one at the bottom, and call it a day. That works right up until someone needs an MRI. The premium is the only cost you’re guaranteed to pay, which makes it feel like the whole story. It isn’t. We built a free FEHB Total Cost Calculator to show the rest of it, and this post explains the math behind it.
Federal Benefits Open Season runs November 9 through December 14, 2026, for coverage in plan year 2027 (OPM, Open Season Highlights, Plan Year 2027).
The short version
- Total yearly cost = (biweekly premium × 26) + expected out-of-pocket costs − any HSA/HRA money the plan puts in.
- A low premium often comes with a higher deductible, higher coinsurance, or a higher out-of-pocket maximum. In a bad year, that can cost more than you saved.
- HDHPs deposit money into an HSA (or HRA) for you. That’s real money, and it belongs in the comparison.
- Run two scenarios, a quiet year and a rough year, and see which plan you can live with in both.
Why premium alone misleads
Your FEHB costs come in three pieces:
- Premium. Your share comes out of every paycheck, 26 times a year, whether you see a doctor or not.
- Out-of-pocket costs. The deductible, then coinsurance (a percentage) or copays, up to the plan’s out-of-pocket maximum. This part depends on how much care you use.
- Plan money. HDHPs pass part of the premium through to an HSA, or an HRA if you aren’t HSA-eligible. Some plans, such as Aetna Direct, have a medical fund that pays your first covered costs.
The premium is fixed. The out-of-pocket part can be small or huge. A plan that saves you $3,000 in premium but has a $2,000-higher out-of-pocket maximum is a good deal in most years and a worse one in very few. You decide whether you can absorb that risk. The calculator just puts numbers on it.
Worked example: GS-12 step 5, Self Only
Take a GS-12 step 5 on the 2026 Rest of U.S. pay table: $101,443 (OPM 2026 salary tables). We compared three 2027 Self Only options, using non-Postal employee premiums from OPM’s 2027 FEHB premium tables and in-network figures from each brochure:
| Plan (enrollment code) | Biweekly premium | Yearly premium (×26) | Deductible | Coinsurance used | In-network OOP max | HSA/HRA |
|---|---|---|---|---|---|---|
| FEP Blue Standard (104) RI 71-005 | $204.65 | $5,320.90 | $500 | 15% | $7,000 | None |
| GEHA HDHP (341) RI 71-014 | $81.62 | $2,122.12 | $1,800 | 5% | $6,000 | $1,000 ($83.33/mo) |
| Compass Rose Standard (424) RI 71-028 | $69.04 | $1,795.04 | $500 | 30% | $9,000 | None |
As a share of base pay, the yearly premium is about 5.2% (FEP Blue Standard), 2.1% (GEHA HDHP), and 1.8% (Compass Rose Standard). On premium alone, Compass Rose Standard wins and FEP Blue Standard looks expensive. Now add care. (Compass Rose Standard is also OPM’s default plan for people whose FEHB option ends in 2027; see what’s new for FEHB in 2027.)
Low-use year: $1,000 of covered in-network care
| Plan | Premium | Out-of-pocket | HSA/HRA | Total |
|---|---|---|---|---|
| FEP Blue Standard | $5,320.90 | $575 ($500 deductible + 15% of $500) | $0 | $5,895.90 |
| GEHA HDHP | $2,122.12 | $1,000 (all deductible) | −$1,000 | $2,122.12 |
| Compass Rose Standard | $1,795.04 | $650 ($500 + 30% of $500) | $0 | $2,445.04 |
In a quiet year, the HDHP’s $1,000 deposit covers the whole bill, and it comes out cheapest even though its premium isn’t the lowest.
High-use year: $30,000 of covered in-network care
| Plan | Premium | Out-of-pocket | HSA/HRA | Total |
|---|---|---|---|---|
| FEP Blue Standard | $5,320.90 | $4,925 ($500 + 15% of $29,500) | $0 | $10,245.90 |
| GEHA HDHP | $2,122.12 | $3,210 ($1,800 + 5% of $28,200) | −$1,000 | $4,332.12 |
| Compass Rose Standard | $1,795.04 | $9,000 (hit the OOP max) | $0 | $10,795.04 |
In a rough year, the plan with the cheapest premium is the most expensive of the three, and FEP Blue Standard’s $3,500 premium gap over Compass Rose Standard mostly comes back to you. Under this simple model, the HDHP wins both years. Before you take that as a verdict, read the limits below. The 5% is GEHA HDHP’s in-network coinsurance after the deductible, but real bills include copays and drug tiers that a single percentage can’t capture. Also, the worst case is what matters here: if everything goes wrong, you pay $6,000 − $1,000 + $2,122.12 = $7,122.12 on the HDHP, versus $12,320.90 on FEP Blue Standard and $10,795.04 on Compass Rose Standard. This is a description of how the math works, not a recommendation. Your doctors, your drugs, and your network can matter more than any of these numbers.
How to use the calculator
- Open the FEHB Total Cost Calculator. It’s free, with no login.
- Choose your enrollment type: Self Only, Self Plus One, or Self and Family.
- Pick up to three plans. Each one fills in its 2027 premium, deductible, out-of-pocket maximum, coinsurance, and any HSA/HRA amount, with a link to its brochure.
- Choose expected use: low ($1,000), medium ($6,000), high ($30,000), or a custom total of covered charges.
- Compare the yearly totals. Then change the spending number and see whether the ranking holds up.
You can override any deductible, out-of-pocket maximum, or coinsurance figure. That’s useful when the brochure shows a different number for the services you actually use.
What the calculator doesn’t do
- In-network only. It uses each plan’s in-network (Preferred/PPO) deductible and out-of-pocket maximum. Out-of-network care usually costs more and often has its own, higher limits.
- One shared family pool. Self Plus One and Self and Family enrollments are treated as one pool against the family deductible and maximum. Most plans also cap each person at a Self Only limit, so your real costs could be lower.
- One coinsurance rate. Real plans mix fixed copays (office visits, ER, drug tiers) with percentages. The calculator uses the plan’s in-network hospital coinsurance from its brochure summary.
- Copay-heavy plans like FEP Blue Basic. Basic has no calendar-year deductible and uses copays (for example, $500 a day for an inpatient stay, up to $3,500) instead of one coinsurance rate. The calculator leaves its coinsurance blank, so you have to enter an estimate from the brochure.
- Not modeled: separate pharmacy deductibles (for example, Aetna Advantage’s), non-covered services, wellness incentives, HSA tax savings, and Postal (PSHB) rates. Premiums are full-year 2027 non-Postal rates.
Before you enroll
Check your shortlist in OPM’s Plan Comparison Tool, then read each plan’s official brochure, especially Section 4 (your costs) and the drug formulary. Confirm your doctors are in network. Then make your change through your agency’s system between November 9 and December 14, 2026. If you need to-dos and deadlines, our Open Season checklist and the 2026 Open Season guide cover them. To see what a premium change does to your paycheck, try the GS-12 paycheck budget. Every tool is on the calculators page.
Sources
- OPM, 2027 FEHB premiums (FFS and HMO tables)
- FEP Blue 2027 brochure, RI 71-005
- GEHA HDHP 2027 brochure, RI 71-014
- Compass Rose Health Plan 2027 brochure, RI 71-028
- OPM, 2026 Open Season Highlights for Plan Year 2027
- OPM, 2026 General Schedule salary tables (Rest of U.S.)
This article is for educational purposes only and isn’t financial, insurance, or legal advice. The High Three isn’t affiliated with OPM or any FEHB carrier. Figures were checked on October 30, 2026; confirm them with OPM and the plan brochures before you enroll.
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