If your company’s group health plan renews on January 1, open enrollment season is closer than it feels. Most small employers set their enrollment window in October or November, with new elections taking effect January 1 of the following year, and benefits advisors generally recommend starting the planning process 60 to 90 days before that window opens. For a calendar-year plan, that means the real work — reviewing plan options, updating payroll deductions, preparing employee communications, and getting compliance notices in order — needs to start now, in September, not in the last week of October.
This is especially true for employers in the 20-to-200-employee range, where there often isn’t a dedicated HR or benefits department to keep track of every moving piece. The good news is that the checklist, while long, is manageable if it’s broken into pieces: what to review with your broker or carrier, what to communicate to employees, and what you’re legally required to distribute.
Start with the plan review, not the enrollment materials
Before anything goes out to employees, it’s worth sitting down with your broker or carrier rep to look at how the current plan actually performed. Did claims run higher or lower than expected? Are employees using the plan the way it was designed to be used, or are they consistently confused about deductibles, networks, or how the HSA or FSA works alongside the medical plan? This is also the moment to revisit whether your funding arrangement still makes sense — fully-insured, level-funded, or self-funded — since a plan that fit a 40-person company two years ago may not fit the same company at 90 employees today.
It’s also the right time to check contribution strategy against the plan’s actual premium trend. Carriers typically release renewal rates in the late summer or early fall for January plans, so by mid-September you should have, or be close to having, a firm renewal number. If the increase is meaningful, this is the window to shop alternate carriers or plan designs, not December.
Know your 2026 numbers before you build employee materials
A few federal limits changed for the 2026 plan year, and getting them into your enrollment materials early avoids a scramble later. The IRS raised HSA contribution limits to $4,400 for self-only coverage and $8,750 for family coverage in 2026, with an additional $1,000 catch-up contribution available to those 55 and older who aren’t yet enrolled in Medicare. Health care FSA limits also rose, to $3,400 for 2026, up from $3,300, and the amount employees can carry over into the next plan year increased slightly as well. Dependent care FSA limits saw a larger jump this year, following a change enacted through recent federal legislation, which is worth flagging clearly to employees who use that benefit since the increase is easy to miss if they’re going off last year’s enrollment guide.
If your company is an applicable large employer under the ACA — generally 50 or more full-time and full-time-equivalent employees — the affordability percentage employers use to test whether the lowest-cost, employee-only plan option is “affordable” rose to 9.96% for 2026, the highest it has been since the ACA’s affordability test began. In practical terms, using the federal poverty line safe harbor, an employer can charge employees no more than roughly $129.89 per month for the least expensive qualifying plan option and still meet that safe harbor. Companies under 50 employees aren’t subject to the mandate itself, but many still use the same affordability benchmarks as a sanity check on their contribution strategy, since it’s a reasonable proxy for what employees can absorb.
Don’t let the required notices become an afterthought
Open enrollment isn’t just a communications exercise — it comes with a handful of federal notice requirements that are easy to overlook when you’re focused on plan design. If your group health plan includes prescription drug coverage, federal law requires you to tell Medicare-eligible employees, dependents, and COBRA participants whether that coverage is “creditable” (meaning it’s expected to pay out, on average, at least as much as standard Medicare Part D coverage) before October 15 each year, ahead of Medicare’s own annual enrollment period. This year carries an extra wrinkle: CMS raised the actuarial value bar used in the standard simplified determination method from 60% to 72% for 2026, reflecting how much richer the Part D benefit itself has become. That means some plans that were creditable last year may not automatically qualify this year without a fresh determination, so it’s worth confirming with your carrier or broker rather than assuming last year’s notice language still applies.
Alongside the Part D notice, plan sponsors are generally expected to distribute a Summary of Benefits and Coverage to enrollees at open enrollment, along with any COBRA, HIPAA, or state-specific notices that apply to your plan. None of these are complicated on their own, but they each have their own timing and delivery rules, and missing one is one of the more common (and avoidable) compliance gaps small employers run into.
Build in time for employee questions
The last piece worth planning for isn’t a deadline at all — it’s time. Employees increasingly expect to understand what they’re choosing between, not just pick a plan name off a list. If you’re offering more than one medical option, or introducing an HSA-eligible plan for the first time, plan on at least one info session or a clearly written comparison sheet that puts premiums, deductibles, and out-of-pocket maximums side by side in plain language. Employers who build in that extra runway tend to see fewer mid-year questions about why a claim wasn’t covered the way someone expected, which saves time for everyone once the plan year is underway.
This post is general information, not legal, tax, or insurance advice. Contribution limits, compliance deadlines, and affordability thresholds should be confirmed with your broker, carrier, or benefits counsel, and any decisions about your specific plan should be based on a review of your actual policy documents.
Sources
- Open Enrollment Checklist 2026: A Step-by-Step Guide for Small Business Owners — Decisely
- Oct. 15 Deadline Nears for Medicare Part D Coverage Notices — SHRM
- October 15 Deadline for Medicare Part D Notice — Newfront
- Medicare Part D Creditable Coverage: CMS Finalizes Revised Simplified Determination Method for 2026 — Risk Strategies
- New ACA Affordability Percentage For 2026 Is 9.96 Percent — Liebert Cassidy Whitmore
- The ACA Affordability Determination in 2026 — Newfront
- IRS Announces 2026 HSA and HDHP Limits — Keenan
- HSA contribution limits and eligibility rules for 2026 and 2027 — Fidelity
- 2026 FSA limits, commuter limits announced — WEX Inc.
- IRS Releases Annual Increases to Health FSA and Transportation Fringe Benefit Limits for 2026 — ERISA Practice Center