If you buy your own health insurance — self-employed, retired before 65, working somewhere without a group plan — Open Enrollment is the one window each year when you can change it without needing a qualifying life event.
It opens November 1. The work that makes it go well belongs in the weeks before, and almost none of it involves looking at plans.
A note on the calendar before anything else: states that run their own exchange set their own dates, and Massachusetts is one of them. The Health Connector’s window has historically run later than the federal one. Check the dates on the exchange you actually use rather than the ones on the news.
One: project next year’s income, not this year’s
The premium tax credit is calculated on your projected household income for the coverage year — not last year’s tax return, not what you are earning today.
This is genuinely hard for anyone self-employed, on commission, or newly retired, and it is where most of the pain comes from. The credit is reconciled on your tax return the following April: estimate too low and you repay, estimate too high and you overpaid all year for nothing.
Work out the number now, while there is time to think about it. The subsidy estimator runs the calculation in your browser, and the complete guide to Marketplace subsidies covers how the arithmetic works and what counts as income.
Two: find out what your current plan does on January 1
Your carrier sends a renewal notice in the autumn. It is the Marketplace equivalent of Medicare’s Annual Notice of Change, and it gets thrown away just as often.
Read it for four things: the new premium, the new deductible, the new out-of-pocket maximum, and whether the plan is being discontinued. If it is, the exchange will usually map you to a replacement plan chosen by an algorithm, not by you.
Three: check the benchmark, not just the plan
This is the part that catches people, and it is worth understanding properly.
Your premium tax credit is pegged to the second-lowest-cost silver plan in your area — the benchmark. That plan changes every year. If a cheaper silver plan enters your market, the benchmark drops, your credit drops with it, and your net premium goes up even though your plan and your income did not change at all.
Automatic re-enrollment keeps your plan, not your price
Doing nothing is not neutral. It is a decision to accept whatever your old plan costs once next year’s credit is applied to it — a number nobody has shown you yet.
The plan that was the best value last year is frequently not the best value this year, for reasons that have nothing to do with you.
Four: run your doctors and your drugs against next year
Networks and formularies reset on January 1, the same as they do in Medicare.
- Doctors and hospitals — confirm against the next year directory, not the one you checked last November
- Prescriptions — check each one against the plan’s formulary for the coming year, with the dose
- Anything already scheduled — a surgery, a course of treatment, an ongoing therapy
If you have a treatment in progress, the network question outranks the premium question by a wide margin.
Five: update the application itself
The exchange application carries details that quietly decide your eligibility, and people forget to update them: household size, marital status, address, immigration status for any household member, and whether anyone has become eligible for employer coverage or Medicare.
An out-of-date application does not just produce a wrong price. It can produce a wrong eligibility determination that takes months to untangle.
Two situations that need their own conversation
Someone in the household is turning 65 next year. Medicare and a Marketplace plan do not sit together comfortably, and the premium tax credit generally stops for that person once they are eligible for premium-free Part A. The Medicare enrollment window checker will give you the dates.
You are losing employer coverage. That is a qualifying event with its own limited window, and it does not wait for November. The COBRA decision in particular has a deadline attached — we walk through it in COBRA or a Marketplace plan, and there is a service page for exactly this situation.
Book it before the first week of November
The opening days of Open Enrollment are the busiest of the year, and the December 15 deadline for January 1 coverage arrives faster than it reads.
A plan comparison costs nothing and takes about twenty minutes: your projected income, your doctors, your prescriptions, and every plan available to you ranked on total annual cost rather than premium alone. Book a time now and hold a slot in the first week.
Frequently asked questions
When does Marketplace Open Enrollment start?
On most exchanges it opens November 1, with December 15 as the deadline for coverage starting January 1 and a mid-January close for coverage starting February 1. States that run their own exchange — Massachusetts among them — set their own calendar, so confirm the dates for the exchange you actually use.
What happens if I do nothing?
Most exchanges will automatically re-enroll you into your current plan, or the closest available one if yours has been discontinued. Your coverage continues, but your premium tax credit is recalculated against the benchmark plan for the coming year, which can move your net premium significantly in either direction.
What if my income changes during the year?
Report it to the exchange as soon as you know. The premium tax credit is reconciled on your tax return against your actual income, so an estimate left uncorrected becomes either a refund or a repayment the following April. Updating mid-year is far less painful than settling up at filing.