Yes. If your organization lets employees pay for health insurance, FSA contributions, or other qualified benefits with pre-tax dollars, federal law requires you to have a written Section 125 plan document in place before those deductions start. Internal Revenue Code Section 125 defines a cafeteria plan as “a written plan,” and the IRS treats an unwritten arrangement as if it never existed.1Office of the Law Revision Counsel. 26 USC 125 Cafeteria Plans Without the document, every pre-tax dollar becomes taxable, and the employer inherits the payroll tax bill.
Why the Document Itself Is What Makes the Plan Real
A Section 125 cafeteria plan is the only legal mechanism that lets employees choose between taxable cash and pre-tax benefits without the choice itself creating tax liability. When elections are valid, salary reductions are excluded from federal income tax, FICA, and FUTA, and the employer avoids its matching share of those payroll taxes.2Internal Revenue Service. FAQs for Government Entities Regarding Cafeteria Plans
All of that hinges on the writing. Section 125(d)(1) defines a cafeteria plan as “a written plan under which all participants are employees, and the participants may choose among 2 or more benefits consisting of cash and qualified benefits.”1Office of the Law Revision Counsel. 26 USC 125 Cafeteria Plans No document, no plan. There is no grace period and no workaround.
The plan document is not the Summary Plan Description. The SPD is the plain-language handout given to employees and is required under ERISA for welfare benefit plans. The Section 125 document is the underlying legal framework that establishes the pre-tax arrangement itself. You need both, but the plan document is what the IRS looks at when deciding whether pre-tax treatment holds up.
The document also has to be adopted on or before the first day of the plan year it covers. You cannot start running pre-tax deductions in January and sign the document in March. Adoption comes first, then the deductions.
What Happens If You Don’t Have One
If the IRS audits and finds no written plan document, or a document missing required provisions, everyone gets hit. Every benefit employees paid for on a pre-tax basis is reclassified as taxable income, potentially reaching back multiple years. Employees owe federal income tax, FICA, and any applicable state taxes on those amounts.
The employer’s exposure is worse. You are on the hook for the employer share of FICA and FUTA on the reclassified wages, plus penalties and interest for failing to withhold and report correctly. Every Form W-2 filed with incorrect wages also triggers separate information-return penalties under IRC Sections 6721 and 6722, which scale by how late the correction is made.3Internal Revenue Service. Information Return Penalties
There is no formal IRS correction program for this. The Employee Plans Compliance Resolution System explicitly excludes “the failure to adopt a written plan” from self-correction.4Internal Revenue Service. EPCRS Overview If you find that your document is missing or was never properly executed, the practical fix is to adopt a compliant document now and operate correctly going forward. That will not erase prior-year liability, but it stops future exposure.
What the Plan Document Has to Contain
The proposed Treasury regulations under Section 125 list the specific provisions every plan document must include.5U.S. Department of the Treasury. Section 125 Proposed Treasury Regulations Missing any of them gives the IRS grounds to disqualify the plan:
- A specific description of each benefit offered, including the periods of coverage.
- Eligibility rules, with a statement that all participants must be employees.
- Election procedures, including when elections are made, what periods they cover, and a statement that elections are irrevocable except on a qualifying change-in-status event.
- How contributions are made: salary reduction, nonelective employer flex credits, or both.
- The maximum salary reduction available to any employee, stated as a dollar figure, a percentage of compensation, or a formula.
- The 12-month plan year, with start and end dates.
- If the plan includes a flexible spending arrangement, provisions addressing the uniform coverage rule and the use-or-lose rule.
- If the plan offers a grace period after the plan year, the terms of that grace period.
The document must also formally name the plan administrator, the person or entity responsible for day-to-day operations and compliance decisions.
Contribution limits that adjust each year, such as the health FSA cap and the dependent care exclusion under IRC Section 129, can be stated as dollar figures in the document or incorporated by reference to the IRS-adjusted amounts.6Office of the Law Revision Counsel. 26 U.S. Code 129 – Dependent Care Assistance Programs If you hard-code numbers, you have to amend the document each time the IRS updates them.
Election Irrevocability and Change-in-Status Events
A core operating rule of any cafeteria plan is that employee elections are irrevocable for the plan year. Once an employee elects during open enrollment, they are locked in until the next enrollment window. The document must say this clearly.
The exception is a qualifying change-in-status event. Treasury regulations list the categories of events that can allow a mid-year change:7eCFR. 26 CFR 1.125-4 – Permitted Election Changes
- Change in marital status: marriage, divorce, legal separation, annulment, or death of a spouse.
- Change in number of dependents: birth, adoption, placement for adoption, or death of a dependent.
- Change in employment status affecting the employee, spouse, or a dependent, including starting or leaving a job, unpaid leave, strike or lockout, or worksite change.
- A dependent aging out, losing student status, or otherwise becoming ineligible.
- A move by the employee, spouse, or dependent that affects benefit eligibility.
The new election has to be consistent with the event. A new baby cannot be used as a reason to drop dental coverage. And the plan document has to list which events the plan actually recognizes, because you are not required to permit all of them, but any you do permit must fit the categories in the regulations. Vague or incomplete language here is a common audit problem.
Nondiscrimination Testing
A cafeteria plan cannot disproportionately favor highly compensated or key employees. Section 125 requires annual testing of the plan’s eligibility rules and how benefits are distributed. Three tests apply: an eligibility test, a contributions-and-benefits test, and a key employee concentration test that caps benefits going to key employees at 25% of the total.
When a plan fails, the tax consequence lands on the highly compensated and key employees, not the rank and file. Their pre-tax elections get reclassified as taxable wages. For a dependent care FSA, if the plan fails the 55% average benefits test, the entire dependent care contribution for every highly compensated employee must be reported as taxable wages on the W-2.
Your document should say how testing will be run and what corrective steps the employer will take on a failure. Most drafters skip this until it becomes a problem.
Simple Cafeteria Plan Safe Harbor for Small Employers
Employers that averaged 100 or fewer employees in either of the two preceding years can set up a “simple cafeteria plan” under IRC Section 125(j) and skip nondiscrimination testing altogether.8Office of the Law Revision Counsel. 26 U.S. Code 125 – Cafeteria Plans The plan is deemed to satisfy the nondiscrimination requirements if two conditions are met.
First, the employer must contribute for each eligible non-highly-compensated, non-key employee at least 2% of that employee’s compensation, or match salary reductions dollar-for-dollar up to 6% of compensation. Second, every employee with at least 1,000 hours of service in the preceding plan year must be eligible to participate. If you qualify, building this structure into the document from the start avoids annual testing entirely.
Keeping the Document Current
The document is not one-and-done. Every time you add or drop a benefit, change eligibility, or adjust the plan year, you need a written amendment. Amendments have to be in writing and can only take effect after the later of the adoption date or the stated effective date. You cannot backdate changes to cover gaps you should have handled earlier.5U.S. Department of the Treasury. Section 125 Proposed Treasury Regulations Retroactive revocations of coverage are never permitted.
The IRS does not formally require periodic restatements of Section 125 documents the way it does for qualified retirement plans. Still, after several rounds of amendments, a document with a stack of addenda becomes hard to administer without contradictions. Consolidating into a clean restatement every few years reduces that risk and gives you something coherent to hand over if the IRS asks to see the plan.
What the Document Does Not Cover
The Section 125 plan itself has no Form 5500 filing requirement. It is a tax mechanism, not an ERISA benefit plan on its own. The underlying benefit plans funded through it, though, may each carry their own ERISA obligations. A self-funded health plan with more than 100 participants at the start of the plan year, for example, generally has its own Form 5500 filing. Do not assume the cafeteria plan document handles everything. It handles the pre-tax election framework. The benefit plans underneath it have their own documents, reporting, and disclosure rules.