Short answer: Under IRS rules, FSA elections generally cannot be changed during the plan year unless a permitted qualifying event occurs and the employer’s plan allows a mid-year change.
The Irrevocable Election Rule applies to Flexible Spending Accounts (FSAs) offered through a Section 125 cafeteria plan. Before the start of each plan year, employees must elect whether to participate in an FSA and decide how much to contribute for that year. Once the plan year begins, that election is generally locked in and cannot be changed until the next open enrollment period.
This rule exists to preserve the tax-advantaged status of cafeteria plans. Allowing unrestricted mid-year changes would undermine the pre-tax framework established under federal tax law.
There are limited exceptions. An employee may be allowed to change an FSA election mid-year if they experience a permitted election change event, such as a change in employment status, a change in marital status, a change in the number of dependents, or certain court orders affecting dependents. Any mid-year change must be consistent with the qualifying event.
Importantly, employers are not required to allow mid-year election changes, even when a qualifying event occurs. Mid-year changes are permitted only if the employer’s cafeteria plan document specifically allows them.
Because of the Irrevocable Election Rule, employees should carefully consider their anticipated medical or dependent care expenses when making FSA elections during open enrollment.
Sources
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Internal Revenue Service, FAQs for Government Entities Regarding Cafeteria Plans
https://www.irs.gov/government-entities/federal-state-local-governments/faqs-for-government-entities-regarding-cafeteria-plans -
Internal Revenue Code, Section 125
- Treasury Regulations §1.125-4 (Permitted election changes)
Content history
Originally published: March 25, 2025
Last reviewed: January 25, 2026