Flex, Pay With HSA/FSA vs WellnessPay HSA/FSA App
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Nov 1, 2026 for Flex, Pay With HSA/FSA, Feb 19, 2026 for WellnessPay HSA/FSA.
The short answer
Head to head
Momentum
New reviews each month
Review pace is the clearest public read on how fast an app is winning new merchants.
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureFlex allows merchants that qualify to accept HSA/FSA as a payment option directly in the checkout flow.
WellnessPay enables Shopify merchants to offer post-purchase HSA/FSA reimbursement for eligible health and wellness products. After checkout, a configurable extension appears on the Thank You page where customers can submit their order receipt. If required, customers complete a brief eligibility questionnaire and receive documentation for reimbursement.
- Accept HSA/FSA payments directly in the checkout flow
- Auto-substantiate during checkout
- Qualify your product with a Letter of Medical Necessity
- Streamlined onboarding into the wellnesspay platform to manage health benefits.
- Integrate purchase receipt details into HSA/FSA eligiblity categorization.
- Allow customers to quickly manage health savings with their insurance provider.
All the numbers
Every figure, side by side
A green dot marks the app ahead on a measured figure. Estimates, gaps and apps that leave no storefront trace never take the lead.
Adoption
| Measure |  WellnessPay HSA/FSA | |
|---|---|---|
| Detected stores | Not published | Not published |
| Net store change, 28 days | 0 | 0 |
| Stores added, 28 days | Not enough data | Not enough data |
| Big-brand share | Not enough data | Not enough data |
| Top store categories | Not published | Not published |
| Top store countries | Not published | Not published |
Reviews
| Measure | WellnessPay HSA/FSA | |
|---|---|---|
| App Store rating | 5.0 ★ | Not published |
| App Store reviews | 7 | Not published |
| New reviews, 28 days | Not enough data | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
Pricing
| Measure | WellnessPay HSA/FSA | |
|---|---|---|
| Free plan | Not listed | Not listed |
| Lowest paid monthly plan | No monthly plan listed | No monthly plan listed |
| Longest free trial | Not listed | Not listed |
| Plans listed | Not published | Not published |
Listing
| Measure | WellnessPay HSA/FSA | |
|---|---|---|
| Shopify category rank | Not enough data | Not enough data |
| Shopify App Charts | Not on this week’s charts | Not on this week’s charts |
| Built for Shopify | No | No |
| Launched | Nov 15, 2023 | Sep 18, 2025 |
| Languages | 1 | 1 |
| Developer | Flex | WellnessPay |
FAQ
Flex, Pay With HSA/FSA and WellnessPay HSA/FSA: common questions
- Where does this comparison’s data come from?
- Shoplist crawls Shopify storefronts to detect which apps each store runs, and reads each app’s Shopify App Store listing for reviews, pricing, features and integrations. Store counts are as of Nov 1, 2026 for Flex, Pay With HSA/FSA, Feb 19, 2026 for WellnessPay HSA/FSA; estimated figures are labeled.
How Shoplist compares apps
Store counts come from Shoplist’s crawl of Shopify storefronts, which detects the apps each store runs; they are as of Nov 1, 2026 for Flex, Pay With HSA/FSA, Feb 19, 2026 for WellnessPay HSA/FSA. Reviews, ratings, plans, features and integrations come from each app’s Shopify App Store listing. 28-day figures are labeled when estimated, and a figure that is missing or estimated never decides who leads. Read the methodology.