Healthcare services · Price transparency
Certainly Health
A New York marketplace that predicted what a doctor visit would cost under your own insurance, then promised to pay the difference if the bill came in higher. Three years later the domain redirects to a cosmetic coaching product.
A $50 boot and a $700 bill
Kevin Chiu hurt his ankle. The doctor fitted him with an orthotics boot and Chiu, who had learned to ask, asked what it would cost. He was led to expect about $50. His insurance company later told him he owed $700.
“I refused to pay, and the provider ended up writing off the difference,” he told Forbes in December 2023. “But the whole experience is an example of the craziness in healthcare billing.”
That is the ordinary American billing surprise: in network, scheduled, nobody breaking a rule. It is also the version federal law does not cover.
What the law actually protects
The No Surprises Act took effect on January 1, 2022. CMS describes its reach precisely: out-of-network bills from emergency visits, from care tied to an in-network hospital or ambulatory surgical center, and from air ambulances. New York’s older state law has the same shape. Good faith estimates are owed to people who do not have or do not use insurance, who may dispute a bill at least $400 above the estimate.
The piece written for insured patients is the advanced explanation of benefits, a personalized cost estimate a plan would send before scheduled care. Congress set it to begin on January 1, 2022. It never began. In a September 2025 letter reported by the Healthcare Financial Management Association, the House Ways and Means Committee wrote that “landmark requirements for upfront and advanced price disclosure before scheduled medical procedures, the AEOB, remains entirely unimplemented.” What did arrive was raw data: under the Transparency in Coverage rule, most plans and issuers have posted pricing for covered items and services since July 1, 2022. That machine readable pile of negotiated rates is what Certainly was built from.
Two marketplace engineers
Chiu studied at Stanford and spent seven years at Uber, where by the company’s account he was a founding member of the Uber Health team that grew to $100m in gross bookings in two years. Daryl Sew studied at Cornell, applied AI to self driving cars at XPeng, then started a YC backed food delivery marketplace that reached $4m in gross merchandise value. Tracxn records Certainly Health, Inc. as incorporated on May 27, 2021. The pair went through Y Combinator’s Summer 2023 batch and launched on Hacker News on August 2, 2023, with about 5,000 NYC doctors listed and four payers supported: Blue Cross Blue Shield, UnitedHealth Group, Cigna and Aetna.
How the guarantee worked, and where it stopped
The prediction had three company-stated inputs: payer published rates, the patient’s eligibility and benefits data, and an online learning model to absorb variance across thousands of plans. The output was not a single price. Archived listing pages from January 2024 render it as “Often up to $189*” for a visit, with line items such as “up to $353*” beneath, each asterisked.
The promise attached to that list and only to that list. The 2023 homepage said it flatly: “Even if your insurance says you owe more, we’ll cover the difference so you never pay any more than the prices we show.” Fierce Healthcare reported the boundary in the same piece: if a provider performs a service not shown in the search results, the patient is on the hook. Forbes reported that complex care such as emergency or surgical procedures was not guaranteed. On the provider side the pitch was collection: Certainly saved the patient’s payment method and paid the practice the full patient responsibility in days. Most doctors on the site had never agreed to any of it. No insurer, reinsurer or capital backstop was ever disclosed, so the risk sat on the startup’s own balance sheet, which the founders said out loud.
What happened next
In December 2023 the company announced $2.3 million led by Pacific 8 Ventures with Y Combinator and other institutional and angel investors. Chiu told VatorNews the plan was to grow from two founders to roughly nine people and extend guaranteed pricing into radiology, labs and cosmetic work.
Archived homepages from February 2024, October 2024 and August 2025 are near identical: a Medical track promising guaranteed out-of-pocket costs, a Cosmetic track promising comparison shopping. Then the balance shifted. The terms of service, last updated June 18, 2025, contain no cost guarantee at all. They disclaim all warranties and provide the services “AS IS”. On March 2, 2026 the Internet Archive recorded certainlyhealth.com returning an HTTP 302 to glowup.certainlyhealth.com. As of September 23, 2026 the root domain returns a 301 to certainlyglow.com, an aesthetics coaching subscription at $99 for the first month and then $19.99 a month. Doctor listing URLs return 404. The provider page and the FAQ still resolve, and the FAQ now covers only cosmetic discounts, prepaid credits and non-refundable Pay Now bookings.
What is proven, and what is still claimed
| Evidence | What the record shows | Source type |
|---|---|---|
| The guarantee, as sold | Patients who booked and owed more than the listed prices would have the difference covered, announced Dec 13, 2023. A patient who owed less was promised a refund within 24 hours. | Company-stated |
| What it excluded | Only services shown in the price table. Fierce Healthcare, Dec 2023: a service performed but not listed falls back on the patient. Forbes, Dec 2023: no guarantee for emergency or surgical care. | Independent |
| Who carried the risk | No insurer, reinsurer or backstop disclosed. The company said it expected to lose money on payouts and limited exposure by leaving high variance procedures off the site. | Company-stated |
| The gap it aimed at | No Surprises Act protections run to out-of-network emergency care, care at in-network facilities and air ambulances. Good faith estimates cover uninsured or self-pay patients, $400 dispute threshold. The advanced explanation of benefits for insured patients, due Jan 1, 2022, was unimplemented in late 2025. | Public record |
| Payouts actually made | No published figure for payouts, claim volume, accuracy or bookings. One podiatrist savings anecdote was given as $850 in August 2023 and $900 in December 2023. | Not found |
| Current terms of service | Updated June 18, 2025. No cost guarantee language. Services “AS IS”, warranties disclaimed, liability capped at fees paid in the preceding three months. | Company document |
| Product state, Sep 23, 2026 | Root domain 301s to certainlyglow.com and doctor listings return 404, while the legacy provider page still promises that patients who book pay 100% of deductible and coinsurance upfront. | Live site differs from live claim |
Read plainly: the diagnosis was right and the mechanism was real. Certainly did what the federal government has not yet managed, turning published negotiated rates into a personalized number an insured patient sees before booking. But the guarantee was narrower than the headline. It covered a named list of codes, excluded the expensive end of medicine, and rested on a seed stage balance sheet rather than any disclosed insurance. What survived into 2026 is the cash pay cosmetic half, where there is no insurance to predict and no surprise bill to guarantee against.
What to watch
- Whether CMS issues good faith estimate and advanced explanation of benefits rules, which would put a federal version of Certainly’s core feature into every plan.
- Whether the legacy provider page and its collection promise are retired, or honored.
- Any Form D, announced round or acquisition. Nothing since December 2023.
- Any published accuracy data. A guarantee with no payout record is a claim, not a result.
In their words
“I refused to pay, and the provider ended up writing off the difference.”
Kevin Chiu, co-founder and CEO, Forbes, December 2023 · Independent
“Even if your insurance says you owe more, we’ll cover the difference so you never pay any more than the prices we show.”
Certainly Health homepage, August 2023 archive · Company
“But it is ultimately the doctor who decides which services you end up getting”
Launch HN post, August 2, 2023 · Founders
“we expect to lose money on the guarantee (paying out to patients) for some time until we figure it out, but we’re limiting the losses by not listing the more complex high variance stuff”
Certainly co-founder, Hacker News, August 2023 · Founder
“Yep, since the pricing data is publicly available, we list mostly non-partnered providers.”
Certainly co-founder, Hacker News, August 2023 · Founder
“Our business model depends on us being accurate”
Kevin Chiu, Fierce Healthcare, December 15, 2023 · Independent
“Ensuring that patients have transparent, personalized cost estimates for their health care is a bipartisan priority.”
Senators Cassidy, Hassan and Marshall, July 2025 letter, quoted by USC Schaeffer · Public record
Related companies
Sources
- Public recordMedical bill rights, No Surprises Act protections
- Public recordHealth Plan Price Transparency
- Public recordSurprise Medical Bills, including Bills for Emergency Services
- Public recordEDGAR company and full text search, Form D
- IndependentAI Startup Guaranteeing Healthcare Prices Raises $2.3 Million
- IndependentCertainly, a free booking platform with upfront prices, clinches $2.3M
- IndependentHealthcare price transparency marketplace Certainly Health raises $2.3M
- IndependentCertainly Health Raises $2.3M
- IndependentThe Unfinished Work of the No Surprises Act
- IndependentCongress pressures CMS to implement No Surprises Act requirements
- IndependentThe No Surprises Act IDR Process: An Early Look At 2025 Data
- IndependentCertainly Health company profile and employee count
- FoundersLaunch HN: Certainly Health (YC S23)
- CompanyCompany and launch pages
- CompanyHomepage and listing page captures, Aug 2023 to Mar 2026
- CompanyTerms of service, provider page and FAQ
- CompanyCertainly Glow subscription page
Profile researched and written by Healthcare Discovery. Last updated September 29, 2026.
