10 Surprising HSA/FSA Eligible Items You Can Buy Online
From sleep trackers to posture gear, here are 10 surprising HSA/FSA-eligible items your pre-tax dollars can cover, and where you can buy them online.
Yulia DerdemezisHead of Marketing at Flex
🚀 Fast Facts: What makes an item a “surprising” HSA/FSA eligible purchase
If you’re searching for HSA/FSA eligible items, the reason these products qualify comes down to three core IRS rules:
Devices that measure or monitor health metrics: including sleep, fertility hormones, metabolic data, growth patterns, posture, and recovery
Items used to treat, manage, or prevent a medical condition, from musculoskeletal pain to sleep disorders to mobility challenges
Products that qualify with a Letter of Medical Necessity, making them eligible even if they look like general wellness tools at first glance
These eligibility pathways are why brands like Oura Ring, Mira, Kizik, Lumen, Forme Science, and more offer products that fall under the category of unexpected and surprising HSA/FSA eligible items.
All of the items featured in this guide are available through the Flex Marketplace, the easiest place to shop for pre-tax eligible products across sleep, fitness, women’s health, metabolic health, posture, and more.
Most people think HSAs and FSAs can only be used for prescriptions, doctor visits, or cold medicine. But in 2025 (and now almost 2026), the world of HSA/FSA-eligible products is much broader, especially as health tech, recovery tools, and at-home diagnostics keep evolving.
If you’re trying to avoid the Use-It-Or-Lose-It crunch (or simply want to spend smarter), here are 10 surprising HSA/FSA-eligible items and why they qualify.
10 surprising HSA/FSA eligible products you can buy online
What it is: A weighted vest engineered specifically for women, with removable plates and an ergonomic design that supports bone density, posture, mobility, and longevity-focused training.
Why it’s eligible: Weighted vests used for improving posture, balance, strength maintenance, or physical-therapy programs are often eligible when tied to bone-health or musculoskeletal treatment.
What it is: A clinical-grade at-home hormone testing system that measures LH, estrogen, and other biomarkers to guide fertility, cycle health, and hormone balance.
Why it’s eligible: Mira is a diagnostic medical device, one of the most straightforward IRS-approved HSA/FSA categories.
What it is: Oura tracks medical-grade metrics such as HRV, body temperature, sleep stages, stress load, and recovery patterns, giving users a full view of sleep health and early health-change indicators.
Why it’s eligible: Oura qualifies as a health-monitoring device that tracks quantifiable metrics used in sleep-health programs and recovery protocols.
What it is: A baby-monitoring system that tracks breathing motion, sleep patterns, growth, and health-related insights that help parents support infant wellbeing.
Why it’s eligible: Devices that track breathing or sleep irregularities are often classified as medical monitoring tools.
What it is: Sleep-improving devices designed to regulate circadian rhythms, address insomnia patterns, support recovery, and reduce stress-related sleep disruption.
Why it’s eligible: Sleep-health tools qualify when used to manage insomnia, sleep irregularities, or circadian challenges under a treatment plan.
What it is: A handheld device that measures your body’s fuel source (fat vs. carbs) to guide nutrition, energy balance, and metabolic flexibility.
Why it’s eligible: Lumen is a diagnostic metabolic device, making it eligible when used to manage metabolic conditions or weight-related health goals.
Hume Health — Metabolic & Behavioral Health Support
What it is: A personalized program that helps people improve metabolic function, glucose regulation, weight stability, and long-term health habits.
Why it’s eligible: When used to address clinically relevant metabolic conditions, Hume Health may qualify with documentation or an LMN.
What it is: Structured, hands-free shoes designed for easier movement, stability, and accessibility, especially for people with mobility limitations, chronic back pain, joint issues, or post-surgery needs.
Why it’s eligible: Adaptive footwear qualifies with an LMN when used to support mobility challenges, orthopedic needs, or chronic pain.
What it is: FDA-registered alignment shirts, bras, and posture gear that retrain upper-body alignment using built-in biofeedback and muscle-engagement technology.
Why it’s eligible: Forme functions as posture-correcting medical apparel, a category recognized under HSA/FSA guidelines, especially when used for spinal alignment or chronic pain.
What it is: A therapeutic red- and blue-light device clinically shown to target acne, inflammation, fine lines, and chronic dermatological concerns.
Why it’s eligible: LED light therapy is a recognized dermatology treatment and qualifies when used to manage diagnosed skin conditions.
Where to shop for the best HSA/FSA eligible items
The easiest place to find HSA/FSA eligible products is the Flex Marketplace.
Flex partners with hundreds of health and wellness forward brands, all of which offer instant pre-tax checkout directly through Flex. That means no reimbursement forms, no guesswork, and no hunting for eligibility rules.
Using HSA/FSA funds can save you 30–40% instantly on eligible products. And with many FSAs operating under the Use-It-Or-Lose-It deadline, knowing what qualifies helps you avoid losing leftover funds.
Flex makes it simple to discover surprising HSA/FSA-eligible items and check out with pre-tax dollars in one seamless experience.
