Rating Area 4 — Middle Tennessee (Nashville): Your Marketplace Guide for 2027

Which counties are in Rating Area 4?

Your county decides your rating area. Tennessee has eight ACA rating areas — groups of counties that insurers use when they file plans and prices. If you live in one of these nine counties, you're in Rating Area 4:

• Cheatham
• Davidson
• Montgomery
• Robertson
• Rutherford
• Sumner
• Trousdale
• Williamson
• Wilson

See the full county-by-county map at Tennessee Counties & Rating Areas.

What this means in plain language: insurers file their plans and prices per rating area. The menu of plans and the premiums you see are set for Area 4 as a whole — not for each county individually. Someone in Davidson County and someone in Trousdale County see the same filed plan menu, even if their local choices feel very different.

⚠️ Important: 2027 carrier availability per area is not yet confirmed

Here's what we know and don't know yet:

• Five insurers are approved to sell 2027 marketplace plans somewhere in Tennessee: BlueCross BlueShield of Tennessee, Celtic/Ambetter, Oscar, UnitedHealthcare, and Alliant. (Cigna exits the Tennessee marketplace on December 31, 2026.)
• What we don't yet know: exactly which of those five will sell in Rating Area 4. Per-area carrier lineups are being confirmed through HealthCare.gov window shopping, and this page will be updated when that's done.
• Do not assume that any particular insurer is selling in your county until you've window-shopped your own ZIP code. The statewide approval is not the same thing as your area's lineup.

Population centers and general market dynamics

(General dynamics — not carrier assignments. No insurer is listed here because per-area lineups are still being confirmed.)

The area centers on Nashville, with Murfreesboro, Franklin, and Clarksville as major secondary hubs. A few dynamics worth understanding:

• Choice follows population density. Davidson, Rutherford, and Williamson counties typically draw more insurers competing on plans; rural counties like Trousdale often have one or two. A thinner menu means each plan's network details deserve extra attention.
• Provider networks matter more outside the metros. Before you enroll, verify that your doctors, your hospital, and your prescriptions are in-network for the specific plan you're considering — not just for the insurer generally.
• If your current insurer doesn't offer plans in your area in 2027, you can still shop on HealthCare.gov during open enrollment (November 1, 2026 – January 15, 2027; December 15, 2026 is the deadline for coverage starting January 1, 2027).

Local enrollment help

• GetCoveredTenn (Tennessee's Navigator program): 1-866-475-7879. Good news here: in-person help is available in seven of this area's nine counties — Cheatham, Davidson, Robertson, Rutherford, Sumner, Williamson, and Wilson. Residents of Montgomery and Trousdale counties get phone or virtual help, which is also free and staffed by trained local Navigators.
• HealthCare.gov: 1-800-318-2596 — the federal marketplace Tennessee uses.

FAQ

Which insurers sell in Rating Area 4 for 2027?

Statewide, five insurers are approved to sell in Tennessee in 2027: BlueCross BlueShield of Tennessee, Celtic/Ambetter, Oscar, UnitedHealthcare, and Alliant. But approval isn't the same as availability in your area — per-area lineups are being confirmed through HealthCare.gov window shopping right now. Window-shop your own ZIP code to see exactly who's selling where you live, and check back here: this page will be updated when the Area 4 lineup is confirmed.

Do prices differ from neighboring areas?

Yes — they can. Insurers file prices per rating area, so identical plans in a neighboring area can cost more or less. Your subsidy amount also depends on your area's benchmark plan price. Always shop your own area; never assume a neighbor's price applies to you.

I'm moving within Tennessee — what changes?

A move is a qualifying life event that opens a 60-day special enrollment period — but your plan menu, prices, and subsidy all reset to your new rating area. Even a move from Nashville to Murfreesboro stays in Area 4, but a move across the area line (say, to Dickson or to Knoxville) changes everything. Shop your new ZIP code as soon as you have a move date, and confirm your providers are in-network under the new area's plans.

Sources

• CMS Geographic Rating Areas page
• Tennessee Department of Commerce & Insurance
• CMS Navigator award summaries

Keep exploring

• Health Insurance by Region — the regional hub
• Tennessee Counties & Rating Areas — the full 95-county index
• The Marketplace — how the marketplace works
• The Tennessee Enrollment Calendar — key dates and deadlines
• Health Insurance in Nashville & Middle Tennessee — the Nashville metro page