Section 125 Plan Document Requirements

Here’s a scenario that plays out more often than you’d think: a company has been deducting health insurance premiums pre-tax for years. Employees are saving money. The employer is saving on FICA. Everything seems fine — until an audit reveals there’s no written plan document. Suddenly, those pre-tax deductions may be reclassified as taxable income, and the employer owes back taxes, penalties, and interest.

A Section 125 plan document is the legal foundation of your cafeteria plan. Without it, your plan doesn’t officially exist in the eyes of the IRS — no matter how long you’ve been running pre-tax deductions through payroll. This article covers exactly what the document must contain, when it needs to be in place, and the mistakes that can invalidate your plan.

Why the Plan Document Matters

The IRS is explicit: a Section 125 cafeteria plan must be in writing. This isn’t a suggestion or a best practice — it’s a legal requirement under IRC Section 125 and the associated Treasury Regulations (Prop. Treas. Reg. §1.125-1).

The plan document serves several purposes:

• Legal authority — it establishes the plan and gives it legal standing
• Defines the rules — what benefits are offered, who’s eligible, how elections work
• Protects the employer — in an audit, it’s your primary evidence of compliance
• Informs participants — employees have a right to know the plan’s terms

If you’re deducting premiums pre-tax without a written plan document, you’re operating a cafeteria plan that technically doesn’t exist. The IRS can disallow the pre-tax treatment, which means back taxes and penalties for both the employer and affected employees.

Required Elements of a Section 125 Plan Document

The IRS requires specific provisions in every Section 125 plan document. Here’s what must be included:

1. Description of Available Benefits

The document must list every benefit available through the plan. This typically includes:

• Health insurance premium deductions (medical, dental, vision)
• Health Flexible Spending Account (Health FSA)
• Dependent Care Flexible Spending Account (DCAP)
• Health Savings Account (HSA) contributions
• Group term life insurance (up to $50,000)
• Any other qualified benefits offered under the plan

Each benefit should be described clearly enough that a participant understands what’s available and how it works.

2. Eligibility Requirements

The document must specify:

• Which employees are eligible to participate
• Any waiting periods before eligibility (e.g., first of the month following 30 days of employment)
• How eligibility is determined (full-time status, hours worked, employment classification)
• Whether part-time, seasonal, or temporary employees are included or excluded

Eligibility rules must be applied consistently and cannot discriminate in favor of highly compensated employees.

3. Election Procedures

The plan document must describe:

• When elections are made — typically during the annual open enrollment period before the plan year begins
• How elections are made — paper forms, online enrollment, or other methods
• The irrevocability rule — elections are generally locked for the plan year
• When changes are permitted — qualifying life events that allow mid-year election changes
• Default elections — what happens if an employee doesn’t make an election (typically no participation)
• New hire elections — the process and timeline for employees who become eligible mid-year

4. Plan Year

The document must specify the 12-month plan year. Common choices:

• Calendar year — January 1 through December 31
• Fiscal year — aligned with the company’s fiscal year
• Benefits renewal year — aligned with the health insurance policy renewal date

Whatever you choose, the plan year determines when open enrollment occurs, when elections take effect, and when FSA grace periods or rollovers apply.

5. Employer Contributions and Funding

The document must describe how the plan is funded:

• Whether the plan is funded solely through employee salary reductions
• Whether the employer makes any non-elective contributions (e.g., employer FSA contributions)
• The maximum amounts available for each benefit (e.g., FSA limits)
• How contributions are calculated and when they’re deducted from pay

6. Benefit Payment and Reimbursement Procedures

For plans with FSAs or other reimbursement components:

• How claims are submitted
• Required documentation
• Reimbursement timelines
• The substantiation process
• How disputes are handled

7. Plan Administrator

The document must identify who administers the plan. This is typically the employer, but day-to-day administration may be delegated to a TPA. The document should name:

• The plan administrator (usually the employer)
• The plan sponsor (also usually the employer)
• Any third-party administrators and their roles

8. Amendment and Termination Procedures

The document must describe:

• How the plan can be amended (who has authority, what notice is required)
• How the plan can be terminated
• What happens to participant benefits if the plan is amended or terminated
• How participants are notified of changes

9. COBRA Rights (If Applicable)

If the plan includes benefits subject to COBRA (health FSA, in particular), the document must address COBRA continuation coverage rights and procedures.

10. HIPAA Privacy and Special Enrollment Rights

For plans that include group health benefits, the document must reference:

• HIPAA special enrollment rights (30-day enrollment period after certain life events)
• Privacy protections for health information

11. Nondiscrimination Testing Provisions

The document should reference the requirement for annual nondiscrimination testing and the consequences if the plan fails testing (reduction of benefits for highly compensated employees).

The Summary Plan Description (SPD)

In addition to the plan document itself, ERISA requires a Summary Plan Description — a participant-friendly version of the plan’s key terms. The SPD must be:

• Written in language that participants can understand (no legalese)
• Distributed to participants within 90 days of becoming eligible
• Updated and redistributed when material changes are made

The SPD typically covers:

• Plan name and type
• Plan administrator’s name and contact information
• Eligibility requirements
• Description of benefits
• How to make elections and file claims
• Appeals process for denied claims
• Participants’ rights under ERISA
• Plan year and effective date

Some plan documents and SPDs are combined into a single document — known as an “SPD/Plan Document” — which satisfies both requirements. This is the most common approach for Section 125 plans.

Timing: When Must the Plan Document Be Signed?

This is critical and non-negotiable: the plan document must be adopted (signed) before the first day of the plan year.

You cannot retroactively establish a Section 125 plan. If your plan year starts January 1 and you sign the document on January 15, those first two weeks of pre-tax deductions are invalid.

Key Timing Rules

• New plans: The document must be signed before the plan year starts. Allow at least 2–4 weeks for document preparation.
• Renewals: If your plan is continuing into a new year with no changes, the existing document carries forward. But if IRS limits changed or you modified the plan design, an amendment should be adopted before the new plan year.
• Amendments: Must be adopted before the effective date of the change. Mid-year amendments are permitted but must comply with election change rules.
• Annual updates: Best practice is to review and update the plan document every year, even if changes are minor (e.g., updated FSA limits).

How to Update Your Plan Document

Plan documents aren’t set-and-forget. They need regular updates to reflect:

• New IRS contribution limits (FSA, HSA, DCAP limits change periodically)
• Regulatory changes (new qualifying life events, coverage mandates)
• Plan design changes (adding or removing benefits, changing eligibility)
• Organizational changes (company name change, new TPA)

Update Methods

Formal amendment: A separate document that modifies specific provisions of the existing plan document. Each amendment should reference the section it’s changing and the effective date.

Restatement: A complete rewrite of the plan document incorporating all previous amendments. Best practice is to restate the full document every 3–5 years for clarity.

Most TPAs handle annual updates as part of their service — updating limits, incorporating regulatory changes, and preparing amendments as needed. If your TPA doesn’t do this proactively, ask why.

Common Mistakes That Can Void the Plan

1. No Plan Document at All

The most basic and most damaging mistake. Without a written document, the plan doesn’t legally exist. All pre-tax deductions could be reclassified as taxable.

2. Plan Document Signed After the Plan Year Started

Retroactive adoption is not permitted. The document must be in place before the first day of the plan year.

3. Plan Document Doesn’t Match Actual Practice

If your document says one thing and your administration does another — for example, the document doesn’t include an FSA but you’re running FSA deductions — that’s a compliance problem. The document must accurately reflect what you’re actually doing.

4. Using a Generic Template Without Customization

A boilerplate plan document downloaded from the internet probably doesn’t match your plan design, eligibility rules, or benefits offerings. Generic documents create gaps that an auditor will find.

5. Never Updating the Document

IRS limits change. Regulations change. Your benefits change. A plan document from 2019 that hasn’t been amended is likely out of compliance in multiple areas.

6. Missing the SPD Requirement

Having a plan document but no Summary Plan Description (or combined SPD/Plan Document) is an ERISA violation. The DOL can impose penalties for failure to provide an SPD upon request.

7. Not Including All Required Provisions

Leaving out required elements — like election procedures, the plan year, or amendment provisions — can jeopardize the plan’s qualified status.

What to Do If You Don’t Have a Plan Document

If you’ve been running pre-tax deductions without a written plan document, here’s how to fix it:

1. Don’t panic, but act quickly. The longer you operate without a document, the greater the exposure.
2. Adopt a plan document as soon as possible. It won’t fix past compliance gaps, but it establishes the plan going forward.
3. Consult a benefits attorney or experienced TPA about the retroactive period. They can advise on potential exposure and remediation options.
4. Consider a compliance review of your entire benefits operation — if the plan document is missing, there may be other gaps. Learn what full compliance requires in our Section 125 compliance guide.

The good news: most TPAs can prepare a compliant plan document in 1–2 weeks. The cost is typically $200–$500 for a standalone document, or it’s included as part of ongoing administration fees.

Checklist: Plan Document Requirements

Use this checklist to verify your plan document is complete:

• Description of all benefits offered under the plan
• Eligibility requirements and waiting periods
• Election procedures (timing, method, irrevocability)
• Qualifying life events that permit mid-year changes
• Plan year specified
• Contribution and funding provisions
• Reimbursement and claims procedures (for FSAs)
• Plan administrator identified
• Amendment and termination procedures
• COBRA provisions (if applicable)
• HIPAA special enrollment rights
• Nondiscrimination testing reference
• Signed and dated before the plan year
• Summary Plan Description available to participants

To understand the broader compliance context, see our Section 125 compliance requirements guide and the Section 125 implementation guide.

Want to check whether your plan document meets current requirements? Talk to David to identify potential gaps.

This guide is for informational purposes and does not constitute tax or legal advice. Consult with a qualified tax professional or benefits advisor for guidance specific to your situation.