If your group health plan renews on January 1, open enrollment is no longer a “fall project” — it’s already on the clock. For employers with 20 to 200 employees, the work of comparing plans, updating payroll deductions, and getting notices out the door typically needs to start 60 to 90 days before the new plan year begins. That means late August and September is exactly the right window to get organized, even though the actual employee enrollment period may not open until November.
Why the timeline is tighter than it feels
Carriers and brokers need lead time to finalize renewal rates, and employers need time to actually evaluate what’s being offered before asking staff to make decisions. Most small businesses run their own internal open enrollment window for two to four weeks, usually landing in November or early December so there’s a buffer before paperwork is due to the carrier and coverage takes effect January 1. Work backward from that: if enrollment closes in early December, plan comparisons, budget decisions, and any plan design changes really need to be locked by mid-October. Waiting until November to start shopping the market puts employers in a reactive position — accepting whatever renewal the incumbent carrier offers because there isn’t time to get competitive quotes.
For employers who want to shop the small group market rather than auto-renew, that lead time matters even more. Getting comparative quotes, checking network adequacy for where employees actually live, and modeling total cost (not just premium, but deductibles and out-of-pocket exposure) is not a same-week exercise, particularly for groups in the 50-plus employee range where plan design choices ripple through payroll and HR systems.
What’s changing for the 2026 plan year
A few federal numbers moved this cycle, and they’re worth building into open enrollment communications now rather than correcting after the fact. The IRS raised the HSA contribution limit for 2026 to $4,400 for self-only high-deductible health plan coverage and $8,750 for family coverage, both up from 2025. Employees 55 and older who aren’t yet on Medicare can still add a $1,000 catch-up contribution on top of those limits. If your plan includes an employer HSA contribution, this is a good moment to confirm whether that contribution plus employee elections could push anyone over the cap, since HSA over-contributions carry tax penalties for the employee.
Health FSA limits are also moving. The IRS increased the 2026 pre-tax health FSA contribution limit to $3,400, and the carryover amount employees can roll into the following plan year rises to $680. If your plan offers a health FSA, both numbers need to be reflected in open enrollment materials and in whatever payroll or benefits administration system handles elections — an outdated limit in enrollment software is a common and avoidable error.
One plan design option worth a second look: telehealth-only coverage that bypasses the HDHP deductible is now permanent policy rather than a temporary relief provision, which gives employers more certainty in offering no-cost virtual care alongside a high-deductible plan without jeopardizing employees’ HSA eligibility. It’s optional, but it’s the kind of low-cost, high-visibility benefit that tends to land well with employees during enrollment.
The notices employers forget
Open enrollment isn’t just a benefits fair and an email blast — it comes with a stack of required notices, each with its own delivery rules, and missing one is a compliance gap that’s easy to overlook in a small HR department. At minimum, group health plan sponsors need to distribute the Summary of Benefits and Coverage, the annual Medicare Part D creditable (or non-creditable) coverage notice, and COBRA election materials for anyone losing eligibility. Larger small employers — generally those with 50 or more full-time equivalent employees — also need to keep next year’s ACA reporting on the radar. Forms 1095-C must be furnished to employees by March 2, 2027, with electronic IRS filing due March 31, 2027, for coverage offered during the 2026 plan year. Building a notice checklist alongside the enrollment calendar, rather than treating it as a separate task, is the easiest way to keep both on track.
Building a realistic enrollment calendar
A workable calendar for a January 1 renewal generally looks something like this: finalize renewal numbers or alternative quotes by mid-October, confirm plan design and any contribution changes by late October, open employee enrollment in early-to-mid November for two to three weeks, and close it with enough runway — typically two to three weeks — before the carrier’s paperwork deadline. Communicating the dates through at least two channels (email plus a posted notice, or a short all-hands meeting) and scheduling a live Q&A session tends to reduce the volume of one-off questions HR fields afterward, and it gives employees who are on the fence about plan changes a real chance to ask before they’re locked into an election.
The cost of waiting
The most common mistake small employers make isn’t a compliance slip — it’s simply starting too late to have real options. When plan comparison starts in November instead of September, there typically isn’t time to solicit alternative quotes, model different plan designs, or negotiate on renewal terms, and the default becomes accepting whatever the current carrier proposes. Starting the process now, even if the actual employee-facing enrollment window is still two months out, is what preserves the ability to make a deliberate decision rather than a rushed one.
Sources
- Open Enrollment Checklist 2026: A Step-by-Step Guide for Small Business Owners — Decisely
- 2026 Open Enrollment Checklist — Bolton
- IRS Announces 2026 HSA and HDHP Limits — Keenan
- HSA contribution limits and eligibility rules for 2026 and 2027 — Fidelity
- 2026 Health FSA Limit Increases to $3,400 — Newfront
- 2026 Health FSA Limits — NIS Benefits
- ACA Reporting: Key Deadlines Ahead — NIS Benefits
- Fast-Approaching Deadlines for ACA Reporting and Similar State Reporting — Venable LLP
This article is general information only and is not legal, tax, or insurance advice. Contribution limits, filing deadlines, and notice requirements can vary by plan and situation. Review your actual plan documents and consult a licensed benefits advisor, accountant, or attorney before making enrollment or compliance decisions.