Employer Guide to Offering Flexible Spending Accounts

Flexible Spending Accounts (FSAs) give employers a structured mechanism to reduce payroll tax liability while expanding pre-tax benefit options for employees. Governed primarily by Internal Revenue Code Section 125 and IRS Publication 969, FSAs carry specific design, contribution, and administrative requirements that employers must navigate before offering them. This page covers the definition and scope of employer-sponsored FSAs, how the plan mechanics work, common implementation scenarios, and the decision boundaries that determine whether a particular FSA type fits a given benefit strategy.

Definition and scope

An FSA is an employer-established benefit plan that allows employees to set aside pre-tax salary dollars to pay for eligible expenses. Because contributions reduce an employee's taxable wages before FICA taxes are calculated, both the employer and the employee avoid payroll taxes on the contributed amount — a structural advantage that makes FSAs attractive even for smaller organizations.

The IRS recognizes three primary FSA types relevant to employer plan design:

  1. Health Care FSA (HCFSA) — covers eligible medical, dental, and vision expenses for the employee and qualifying dependents.
  2. Dependent Care FSA (DCFSA) — covers qualifying childcare and dependent care costs that allow the employee (and spouse, if applicable) to work.
  3. Limited-Purpose FSA (LPFSA) — restricted to dental and vision expenses; designed to coexist with a Health Savings Account (HSA).

For a full taxonomy of FSA types and their expense categories, the FSA and HSA: Can You Have Both? page details the compatibility rules between account types.

The employer is the plan sponsor. The FSA must be offered through a Section 125 cafeteria plan (IRS Publication 15-B), which is the legal vehicle that makes employee salary-reduction contributions non-taxable. Employers without a written cafeteria plan document cannot lawfully offer pre-tax FSA contributions.

How it works

Establishing an employer FSA involves a defined sequence of administrative and compliance steps:

  1. Adopt a written Section 125 plan document. The document must specify plan year dates, eligible employees, available benefits, and contribution limits. The regulatory context for health savings provides an overview of the statutory framework governing these requirements.

  2. Set the employer contribution strategy. Employers may contribute to employee FSA balances, but contributions are not required. For Health Care FSAs, the 2024 IRS salary-reduction limit is $3,200 per employee (IRS Revenue Procedure 2023-34). Employer contributions count toward this ceiling only if the plan specifies they do.

  3. Configure the use-it-or-lose-it rule and optional relief provisions. Under IRS Notice 2005-42 and IRS Notice 2013-71, employers may choose to offer a grace period of up to 2.5 months after plan year end, or a carryover of up to $640 (2024 indexed amount) (IRS Notice 2013-71). Employers cannot offer both the grace period and the carryover simultaneously.

  4. Engage a third-party administrator (TPA) or FSA vendor. Most employers use a TPA to issue FSA debit cards, process claims, manage substantiation requirements, and generate required IRS reporting. The mechanics of FSA debit card usage are covered in the FSA Debit Cards: How They Work reference.

  5. Conduct open enrollment. FSA elections must be made before the plan year begins. Mid-year changes are permitted only upon a qualifying life event as defined under Treasury Regulation § 1.125-4.

  6. Administer the uniform coverage rule for HCFSAs. An employer must make the full annual Health Care FSA election amount available on day one of the plan year — even though the employee has not yet contributed that full amount through payroll deductions.

Common scenarios

Scenario 1 — Small employer without HDHP: A small business offering a traditional PPO health plan can offer a Health Care FSA without any conflict, since the HDHP-only eligibility restriction applies to HSAs, not FSAs. Employees contribute up to the IRS limit and receive the full balance on January 1.

Scenario 2 — Employer with HSA-eligible HDHP: When the primary medical plan is a High-Deductible Health Plan (HDHP), a standard Health Care FSA would disqualify employees from contributing to an HSA. The correct structure is a Limited-Purpose FSA, which covers only dental and vision expenses and preserves HSA eligibility under IRS guidance.

Scenario 3 — Dependent Care FSA for working parents: A DCFSA allows employees to exclude up to $5,000 per household annually from gross income (married filing jointly or single filer) to pay for qualifying childcare (IRS Publication 503). This is separate from the Dependent Care Tax Credit, and employees cannot claim both for the same expenses.

Scenario 4 — Carryover vs. grace period election: An employer with historically low FSA utilization may choose the carryover option to reduce forfeitures and improve employee satisfaction with the benefit. An employer whose employees cluster expenses in Q1 of the following year may find the grace period more structurally useful.

Decision boundaries

The choice among FSA types and features turns on three concrete variables:

Decision Factor Health Care FSA Dependent Care FSA Limited-Purpose FSA
HSA compatibility Incompatible Compatible Compatible
Expense scope Medical, dental, vision Qualifying dependent care Dental and vision only
2024 employee contribution cap $3,200 $5,000 (household) $3,200
Employer funding allowed Yes Yes Yes
Uniform coverage rule applies Yes No Yes

Employers offering both an HSA-eligible HDHP and an FSA must structure the FSA as Limited-Purpose to avoid disqualifying employees from HSA contributions — a constraint codified in IRS Notice 2004-50. For employers who want to understand how FSA structure fits within the broader benefit account landscape, the home page provides orientation across all major health savings account categories.

Dependent Care FSAs do not trigger the uniform coverage rule, meaning an employer may not advance the full annual DCFSA balance at the plan year start. Reimbursement is limited to the amount actually in the employee's DCFSA account at the time of the claim — a structural distinction from the Health Care FSA that affects employee communications and plan design documentation.

Nondiscrimination testing is a mandatory compliance requirement for FSAs under IRC §§ 105(h) and 129(d). Plans that disproportionately benefit highly compensated employees risk disqualification of the tax-preferred status for those participants. Employers with concentrated higher-earning workforces should build nondiscrimination testing into annual plan administration.

References

The law belongs to the people. Georgia v. Public.Resource.Org, 590 U.S. (2020)