Technically Compliant: How Some Hospitals Make Their Prices Hard to Find
Since 2021, the federal Price Transparency Rule has required every US hospital to publish its prices in a machine-readable file. We process these files from 136 Texas hospitals twice a week. Most hospitals make this straightforward: download a file, find your procedure, see the price. Not all of them.
What straightforward compliance looks like
The CMS rule requires hospitals to publish a machine-readable file containing gross charges, cash prices, and payer-specific negotiated rates for every item and service. The intent is that patients, researchers, and third-party tools can download the file, read it, and compare prices.
Most of the 136 Texas hospitals we process do this in a way that works. Their files are accessible, use standard formats, and are structured around the procedures patients actually search for:
- Houston Methodist: One JSON file, 69 MB, 29,585 items organized by procedure code. No access restrictions.
- Memorial Hermann (12 hospitals): One CSV per hospital, 34 MB average, 131,000 rows. Standard HTTP access.
- HCA Houston (12 hospitals): Per-hospital JSON files, 940 MB to 1.8 GB. Large, but organized by procedure with 390,000+ items.
- BSW / Baylor Scott & White (16 hospitals): Per-hospital JSON files with dollar-based fee schedules. Standard access.
These files range from 34 MB to 1.8 GB. Some are large. But the data is structured so that finding the price of a specific procedure is feasible with standard tools.
The Ascension Seton experience
When we tried to add Ascension Seton's 12 Austin-area hospitals to our database, we encountered a different experience. Ascension is the largest Catholic hospital system in the United States, operating 140 hospitals across 19 states. In Central Texas, their facilities include Dell Seton Medical Center (Austin's only Level I trauma center) and Dell Children's Medical Center.
The pricing data is there. Once we got to it, the file contains negotiated dollar amounts for 98% of entries and cash prices for 95%. The data quality is comparable to other hospital systems. The difficulty is in getting to it.
1. The URL redirects to a different file type
Every hospital registers a URL with CMS pointing to its pricing file. Ascension Seton's registered URLs end in .csv, indicating a simple spreadsheet. When you request the file, the server returns an HTTP 308 redirect to a different URL ending in .zip.
Any tool or researcher following the CMS registry and expecting a CSV will encounter an error. Other major Texas hospital systems serve exactly the file type their URL indicates.
2. Automated access is blocked
The entire point of a machine-readable file is that machines can read it. Ascension's server checks the User-Agent header of every request. If it detects an automated tool rather than a web browser, it returns HTTP 406 (Not Acceptable) and refuses to serve the file.
Any data pipeline, price comparison tool, or academic researcher using standard HTTP libraries will be blocked without explanation.
3. 404,000 procedure prices are buried inside 15.5 million rows
Once past the redirect and the access block, you download a 245 MB ZIP. Inside is a single CSV that decompresses to 3.9 GB containing 15.5 million rows. That is the pricing file for a single hospital.
Ascension registers 12 separate URLs with CMS (one per hospital), and each serves a file of roughly the same size. Processing all 12 Austin-area hospitals requires downloading nearly 3 GB of compressed data and decompressing roughly 47 GB of CSV.
Of those 15.5 million rows, 96.4% are internal chargemaster (CDM) codes: individual supply items like screws, drug units, and billing components. Only 404,599 rows (2.6%) use the CPT and HCPCS procedure codes that patients and insurers use to identify procedures like an MRI, a colonoscopy, or an ER visit.
A patient looking for the price of a brain MRI at Ascension Seton would need to download 245 MB, decompress 3.9 GB, and search 15.5 million rows to find the handful of entries coded as CPT 70551. At Houston Methodist, the same search is a 69 MB download and a text search through 29,585 items.
Decompressed file size per hospital (single facility)
Ascension Seton's file is 57x larger than Houston Methodist's. 96.4% of its rows are chargemaster line items, not procedure-level pricing.
Source: CMS transparency files downloaded on April 16, 2026. File sizes are decompressed.
What the prices show once you find them
After getting past the access barriers and filtering to the procedure codes patients actually search for, the pricing data at Ascension Seton Medical Center Austin is comparable to other Texas hospitals in scope and quality. Here is a sample:
| Procedure | Cash price | Lowest negotiated | Highest negotiated |
|---|---|---|---|
| MRI Brain (70551) | $1,493 | $163 | $1,969 |
| ER Visit Level 5 (99285) | $2,007 | $200 | $5,800 |
| CT Abdomen/Pelvis (74177) | $3,447 | $229 | $4,309 |
| Knee Replacement (27447) | Not listed | $969 | $14,153 |
| Basic Metabolic Panel (80053) | $95 | $9 | $119 |
An uninsured patient paying cash for an ER visit at Ascension Seton would pay $2,007. Some insurers have negotiated rates as low as $200 for the same visit. That is a 10x difference. For knee replacement, Ascension does not publish a cash price. Humana Exchange pays $6,640 while Humana PPO pays $14,153 for the same procedure at the same hospital.
These spreads are not unique to Ascension. Similar variation exists at Houston hospitals and across Texas insurers. What is different is how much work it takes to find the numbers.
Why the file is 57x larger
The CMS rule requires hospitals to publish prices for "all items and services." Hospitals interpret this differently. Most Texas hospitals we process publish pricing at the procedure level: the codes insurers and patients use to identify specific medical services. Ascension Seton publishes at the chargemaster level: every individual supply item, drug unit, and billing component in their internal system.
Both approaches can be considered compliant. The chargemaster approach produces more data. Whether it produces more useful data depends on who is reading the file.
A patient comparing MRI prices across hospitals needs procedure-level data. A health policy researcher studying drug pricing might find the chargemaster detail valuable. But combining both into a single 3.9 GB file means that neither audience gets what they need without significant processing.
The question of access
The file size is one issue. The access barriers are another. A URL that redirects to a different file type and a server that blocks automated tools are not related to what data the file contains. They affect who can get to it.
The CMS rule specifically requires files to be accessible "without barriers to access, including but not limited to ensuring the file is not behind a firewall." Whether User-Agent filtering constitutes a "barrier to access" under this definition is a question for CMS enforcement.
As of April 2026, CMS penalties for non-compliance can reach $5,500 per day for large hospitals.
What patients can do
If you are planning a non-emergency procedure at any hospital, you have the right to see prices before you schedule. Under the No Surprises Act, hospitals must provide a good faith estimate to uninsured and self-pay patients. Call the billing department and ask for a written estimate.
Compare prices across hospitals. The same MRI that costs $1,493 cash at one hospital might cost $232 at another hospital in the same city. The same ER visit billed at $2,007 to a cash patient might be $200 under certain insurance plans.
We process pricing files from 136 Texas hospitals and display the results in a format designed to be useful. Compare by procedure, hospital, or insurance plan.
We are working to extract the procedure-level pricing from Ascension Seton's files and add their 12 Austin-area hospitals to our comparison tool. When that data is live, we will update this page.