Client Care FAQ's

FSA/HSA FAQs

• What is Flex and what is their relationship with Dr Dennis Gross?

  Dr Dennis Gross has partnered with Flex to allow you to use your Health Savings Account (HSA) or Flexible Spending Account (FSA). This means you can now use your HSA or FSA debit card to buy Dr Dennis Gross products with pre-tax dollars, resulting in net savings of 30–40%, depending on your tax bracket.

• What is an HSA/FSA Account?

  Health Savings Accounts (HSA) and Flexible Spending Accounts (FSA) are tax-advantaged savings accounts that help you pay for qualified healthcare expenses. HSAs are paired with high-deductible health plans and roll over year to year, while FSAs are employer-sponsored and typically must be used within the plan year.

• How do I pay with my HSA or FSA card?

  To use your HSA or FSA debit card, add products to your cart as usual on drdennisgross.com. At checkout, select “Flex | Pay with HSA/FSA” as your payment option, enter your HSA or FSA debit card, and complete your checkout.

• What if I don’t have my HSA/FSA card available?

  If you don’t have your HSA or FSA card handy, still select “Flex | Pay with HSA/FSA” as your payment method. Enter your credit card information instead. Flex will make your itemized receipt available on the consumer portal at app.withflex.com, which you can download and submit to your HSA/FSA provider for reimbursement.

• Why is my HSA/FSA card being declined?

  HSA/FSA cards are debit cards, and the most common reason for declines is insufficient funds. Reach out to your HSA/FSA administrator to confirm your balance.

• I would like to use multiple HSA/FSA cards to pay for an item. Can I do that?

  No, unfortunately, this isn’t a supported feature right now. If there are insufficient funds in a single HSA or FSA account, you can instead enter a credit card on the Flex checkout page. You will receive an itemized receipt and/or Letter of Medical Necessity from Flex, which you can download from the consumer portal at app.withflex.com and submit for reimbursement.

• If I do not have enough funds in my HSA/FSA account to cover my purchase in full, can I still use Flex?

  Yes. If your HSA/FSA card doesn’t have enough to cover the full amount, you can select Flex at checkout and use a regular credit or debit card instead. Flex will make your itemized receipt and, if applicable, a Letter of Medical Necessity available on the consumer portal at app.withflex.com. You can download these and submit them to your HSA/FSA provider for reimbursement.

• Is sales tax covered by HSA/FSA funds, or is it treated separately?
  Sales tax for eligible items is also covered by HSA/FSA funds. If you have a split cart with both eligible and non-eligible items, the tax will be divided among the cards based on the items.
• Do I need a prescription to purchase products with HSA/FSA dollars?
  No prescription is needed. For products that require documentation, Flex facilitates a brief, chat-based telehealth consultation as part of the checkout process to generate the necessary Letter of Medical Necessity. No separate prescription or doctor’s visit is required.
• Where can I find my itemized receipt and Letter of Medical Necessity?

  All of your Flex documents — including your itemized receipt and Letter of Medical Necessity (if applicable) — are available on the Flex consumer portal at app.withflex.com. Log in using the same email address you used at checkout to view and download your documents.

• I logged into the consumer portal but it’s blank — I don’t see any documents.

  The most common reason is an email mismatch. The portal only shows documents tied to the email address used at the time of checkout. Please confirm you’re logging in with the same email you used when making your [BRAND] purchase. If you’re using the correct email and still don’t see your documents, please contact support@withflex.com for assistance.

• When will my documents be available on the portal?
  Your itemized receipt and Letter of Medical Necessity (if applicable) are typically available on the consumer portal at app.withflex.com within 24 hours of your purchase. If you don’t see them after 24 hours, please contact support@withflex.com.
• What is a Letter of Medical Necessity?

  A Letter of Medical Necessity (LOMN) is a document from a healthcare provider that explains how a specific product is medically necessary for a patient to treat a diagnosed condition. Some products require this documentation to qualify for HSA/FSA purchase. If a product requires a LOMN, Flex facilitates a chat-based telehealth consultation during checkout that generates the letter automatically.

• Why do I need to provide health information at checkout?

  In order to qualify to use your HSA or FSA card for certain products, the IRS requires you to have a Letter of Medical Necessity. Dr Dennis Gross has partnered with Flex to enable telehealth consultations as part of the checkout process. Your LOMN and itemized receipt will be available on the consumer portal at app.withflex.com within 24 hours of your purchase.

• Do all products require a Letter of Medical Necessity?

  No. Some products are auto-substantiated, meaning they are pre-approved for HSA/FSA purchase without a LOMN (for example, sunscreen SPF 15+, first aid supplies, and certain medical-grade skincare products). For these items, you simply pay with your HSA/FSA card at checkout — no consultation is required. Flex automatically determines which products need a LOMN and which do not.

• Do I need to do anything with my Letter of Medical Necessity?

  You should keep it on file for at least three years in the event of an IRS audit of your HSA or FSA account. Occasionally, FSA providers may ask for the letter to confirm the eligibility of your purchase. You can download it anytime from the consumer portal at app.withflex.com.

• Can I use a Letter of Medical Necessity from my own doctor?

  Flex’s built-in telehealth consultation is the fastest way to get your LOMN, but if you already have a letter from your own doctor that covers the product you’re purchasing, you may be able to submit it to your HSA/FSA provider. Contact your HSA/FSA administrator to confirm what documentation they accept.

• I mistakenly entered my name and/or date of birth incorrectly. How do I get a corrected letter?

  Please email support@withflex.com with the correct information. The Flex team will update your letter and make the corrected version available on the consumer portal at app.withflex.com.

• The date on my Letter of Medical Necessity is one day different from my receipt.

  This is typically a timezone issue. Please email support@withflex.com and the team will work to reissue the letter with the correct date.

• My FSA says I need additional information (product name, NPI number, etc.) added to my letter.

  Please forward the details of your FSA provider’s request to support@withflex.com. The Flex team will review and work to accommodate your request where possible.

• My product is auto-substantiated but my FSA is still denying my claim. What can I do?

  Some products are pre-approved for HSA/FSA and don’t require a traditional LOMN. If your FSA is denying a claim for an auto-substantiated product, please email support@withflex.com. Flex can provide an auto-substantiation letterhead document that explains why the product qualifies for HSA/FSA without a LOMN, which you can submit to your FSA provider.

• My HSA/FSA claim was denied. What should I do?

  Please forward any denial details or response from your HSA/FSA provider to support@withflex.com. The Flex team will review and advise on next steps. Please note that employer-sponsored FSAs can determine what products are eligible beyond the IRS’s guidelines, so it’s important to check with your provider prior to purchase if you’re unsure about coverage.

• I submitted my itemized receipt for reimbursement and my FSA requires more information.

  Please forward the details of your FSA provider’s request to support@withflex.com and the Flex team will help with your request.

• My Receipt and FSA Charge Don’t Match. How Can I Resolve This?

  We apologize for the discrepancy. Please email support@withflex.com with details and they will review the charges and work to resolve any discrepancies.

• Is sales tax covered by HSA/FSA funds?

  Yes. Sales tax for eligible items is also covered by HSA/FSA funds. For split carts with both eligible and non-eligible items, the tax is divided proportionally among payment methods.

• Can I get reimbursed for an older order that wasn’t placed through Flex?

  Unfortunately, for purchases made without using Flex at checkout, it may be difficult to apply for reimbursement without the proper documentation. For Health Savings Accounts (HSAs), consumers can use an itemized receipt for reimbursement at any time, even years later. For Flexible Spending Accounts (FSAs), most accounts require that the purchase was made within the coverage year. Check with your specific plan for details.

• What happens if I need to return an HSA/FSA eligible item?

  Refunds are processed back to the original payment method. If you paid with an HSA/FSA debit card, the refund will be returned to that card. If you paid with a credit card and already submitted for reimbursement, please contact your HSA/FSA provider about the returned funds. For any issues with the refund process, email support@withflex.com.

• Need Help?

  For any HSA/FSA payment, receipt, or LOMN issues, customers should contact Flex directly at support@withflex.com.

  Customers can access their documents anytime at app.withflex.com using the email address they used at checkout.

  For Dr Dennis Gross order, shipping, or product questions, customers should contact Dr Dennis Gross support directly.