Your Health Plan Auto-Renews on December 15. The Formulary May Have Changed.
Doing nothing during open enrollment is a choice, and this year it is an expensive one. The plan renews at whatever it costs in 2027, on a drug list that was quietly rewritten while you weren't reading. The letter that told you lives in the pile with the takeout menus.
The Letter Nobody Opens
It comes in September or early October, in an envelope that looks exactly like the ten other envelopes your insurer sends you a year. You know the ones. You have trained yourself to ignore them, because most of them are receipts for things you already knew about. This one is not a receipt. It is the only document that tells you what your plan will actually cost and cover starting January 1, and it is sitting under a takeout menu on your counter right now.
Here is the part that makes this year different. If you do nothing, you do not lose your coverage. You keep it, at whatever it costs in 2027, on whatever drug list the plan decides to carry. Doing nothing feels safe. It is the opposite of safe. It is agreeing, in advance, to terms you have not read.
Auto-Renewal Is a Real Thing, and It Has a Date
HealthCare.gov may automatically re-enroll eligible consumers who do not actively choose a 2027 plan, sometimes into a mapped plan if their current one ends. Employer elections follow each plan's rules, so check your benefits notice instead of assuming silence keeps every benefit. In both cases, the system may treat silence as yes.
For a 2027 plan through HealthCare.gov, open enrollment runs November 1 through December 15, 2026. State-run exchanges may set a different period within federal rules. After the deadline, you generally need a qualifying life event to enroll outside open enrollment; check your Marketplace for the next opportunity and start date. The date is not a suggestion. It is the whole game.
The Formulary Is the Part That Moved
A formulary is the list of drugs your plan agrees to pay for, and which tier it puts each one on. It is managed by a pharmacy benefit manager, the PBM, and it is rewritten every year. A drug that sat on tier 2 with a $30 copay this year can move to tier 3 with coinsurance next year, which means you pay a percentage of the full price instead of a flat fee. Same pill. Same pharmacy. Different math.
Drugs also fall off the list entirely. When a formulary drops a medication, the plan stops covering it, and the appeal process to get an exception is exactly as pleasant as it sounds. If you take a maintenance drug, a GLP-1, a brand-name inhaler, a specialty medication, the single most valuable thing you can do this month is find your exact drug on next year's formulary and confirm the tier. Not the drug class. The specific NDC on the bottle.
What the SBC Tells You in Two Pages
Every plan has to give you a Summary of Benefits and Coverage, the SBC, in a federally standardized format. It is boring on purpose, which is its best feature: because every plan's SBC uses the same boxes, you can lay two of them side by side and actually compare. The deductible is in the same spot. The out-of-pocket maximum is in the same spot. The coverage examples, what a plan pays for a routine birth or managing diabetes, are computed the same way for every carrier.
Read three numbers first. The premium, which is what you pay monthly whether or not you use the plan. The deductible, which is what you pay before the plan pays anything. And the out-of-pocket maximum, which is the worst case, the ceiling on what a catastrophic year can cost you. A plan with a $0 premium and a $9,200 out-of-pocket maximum is not a free plan. It is a bet that you will not get sick, and the house wrote the odds.
Two Things Changed Above Your Head This Year
First, the enhanced premium tax credits that expanded marketplace assistance expired at the end of 2025. KFF estimated that this change would raise Marketplace enrollees' 2026 premium payments by an average of 114 percent, about $1,016 for the year. That is a 2026 estimate, not a forecast of your 2027 renewal; use the amount on your own notice. If your subsidy shrank, the plan you auto-renew into may not cost what you expected.
Second, for 2027, CMS no longer requires insurers using HealthCare.gov to offer standardized plan options or labels them that way on the federal site. Insurers may continue offering former standardized options, and state exchanges may differ. Do not expect the old federal labels to do the comparison for you; read each plan's SBC. The choices and costs may change at once, making that work more consequential.
The Three Calls to Make Before December 15
Call one: your pharmacy. Ask them to run your current prescriptions against next year's plan and tell you the 2027 copay for each. They do this all day.
Call two: your doctor's billing office, not the front desk. Ask whether they will still be in-network under your plan for 2027, because networks change quietly and a specialist who drops out costs you far more than a premium bump.
Call three, if you are on the marketplace: HealthCare.gov or your state exchange, to re-run your subsidy with your current income. The credit is recalculated every year, and the number you assumed is the number from a program that no longer exists in the same form. Make the calls. The plan is not going to call you.