Flexible Spending Account (FSA) Unsubstantiated Claims Process

When you receive notices from Optum, the 2025 Flexible Spending Account (FSA) Administrator, about unsubstantiated claims, substantiate, substitute, or repay your unsubstantiated claims, preferably by December 31st. This page includes information on how to resolve your 2025 claims and a timeline of what will occur in 2026 if you do not resolve your claims timely.

Basics of Healthcare FSA Unsubstantiated Claims

If a health care FSA payment card transaction is not automatically substantiated, you will be notified of an “unsubstantiated claim” that needs to be resolved by substantiation, substitution, or repayment. You will receive notices about the unsubstantiated claim via the email address associated with your Optum account:

  • 10 days after the transaction
  • 40 days after the transaction
  • 70 days after the transaction

If your claims are not resolved within 85 days, your payment card will be deactivated (until your claims are resolved). Check the junk folder in your email for these notices. If you do not have an email address associated with your Optum account, the notices will be sent via U.S. Mail.

The FSA administrator sends these notifications for every health care FSA unsubstantiated claim throughout the year.

Resolving Your Unsubstantiated Claims

To avoid the payroll withholding process, 2025 healthcare FSA claims must be resolved by December 31, 2025. To resolve a claim, you should do one of the following:

  • Substantiate the original claim with documentation. Documentation may include:
  • Substitute the original claim with another eligible expense. A substituted claim cannot be a claim previously submitted, and must be for the 2025 plan year.
  • Repay the amount of the claim directly to Optum. To do so, log into your account, or contact Optum to walk you through this option.

You may submit documentation to resolve your claims using the Optum mobile app or the Optum website.

Communications

If you have unsubstantiated FSA claims, additional communications are sent toward the end of the plan year. Notifications are sent to the email or mailing address associated with your account.

Payroll Withholding Process

In January, Optum provided a report to the Universities of Wisconsin with employees with health care FSA unsubstantiated claims (incurred on/prior to 12/31/2025). The report is used for the payroll withholding process.

The Universities of Wisconsin will send an email to the affected employees to make them aware of the payroll withholding process, and that it will continue through March (even if claims are substantiated during the process). Payroll deductions will occur as follows:

Claims Amount Action
At or less than $100 The claims amount will be deducted from the 2/5/2026 paycheck.
Greater than $100 The claims amount will be divided by four and deducted from four paychecks.

  • 02/05/2026
  • 02/19/2026
  • 03/05/2026
  • 03/19/2026

Frequently Asked Questions

I substantiated my claims a few days ago. Why did I receive the payroll withholding email?

The substantiation and payroll withholding processes are complex. There is a chance your claims have been resolved; however, you also appeared on the unsubstantiated claims report. This is likely a timing issue. Payroll withholdings will need to occur for all of the pay dates listed above. If necessary, after March 31st, a refund will be issued directly to you by Optum.

May I resolve unsubstantiated claims during the payroll withholding process and if so, how?

Yes. You may resolve unsubstantiated claims until March 31, 2026 but you will be included in the payroll withholding process. Refer to the “Resolving Healthcare FSA Unsubstantiated Claims” section above for additional information. If necessary, after March 31st, a refund will be issued to you by Optum.

I used my payment card in November and December, and have started to receive notifications from Optum to resolve my claims. If I did not resolve my claims by December 31, 2025, will I be part of the payroll withholding process?

Yes, if you did not resolve your claims by December 31, 2025, you will go through the payroll withholding process.

Why should I resolve unsubstantiated claims after the payroll withholding process has begun?
If you substantiate your claims, a refund will be issued to you by Optum.

What if the payroll withholding process will cause me a significant financial hardship?
If the payroll withholding process will cause you a significant financial hardship, reach out to your benefits contact to determine if other options are available.

Inactive Employees

If you are no longer an active employee:

  • You are responsible for updating your email and mailing address directly with Optum.
  • If you do not resolve an unsubstantiated claim, it will be converted to business debt.

Questions

For questions on how to resolve a health care FSA unsubstantiated claim, eligible expenses, or the status of a claim, contact Optum at (833) 881-8158 or visit the Optum mobile app or the Optum website.

Updated: 01/23/2026

Every effort has been made to ensure this information is current and correct. Information on this page does not guarantee enrollment, benefits and/or the ability to make changes to your benefits.