Same Scan, Same City, Same Insurer — One Fee Schedule Pays 4.23× Another

Pull one insurer's published imaging rates for a single metro and look at what it pays for the most ordinary scan on the list — a head CT without contrast, CPT 70450. In BlueCross BlueShield of Tennessee's in-network home-network file for the Nashville area, the two most common standard rates for that scan are $81.74 and $346.05. Same code, same payer, same city, same component of the service. One is about 20% below Medicare. The other is more than three times Medicare. And each of those two prices is carried, to the cent, by thousands of different providers — about 2,700 at the low rate and about 3,000 at the high one.

That is not the footprint of negotiation. Thousands of unrelated providers do not independently negotiate their way to the identical rate down to the penny. It is the footprint of a fee schedule — a rate table the payer assigns providers onto. We took an earlier look at a single one of these shared schedules in this file. The fuller picture is more useful, and more unforgiving: there isn't one standard schedule. There are several, stacked at wildly different levels, and which one you land on decides almost everything about what you're paid.

Five standard rates, one identical scan

For each of ten common imaging codes, the five most frequent rates are each shared by roughly 1,800 to 3,600 providers. Here is the lowest and highest of those five standard rates for each code, graded against the 2026 Medicare fee schedule:

Read the middle column first, because it is the whole story. On nine of the ten codes the top standard schedule is 4.23 times the bottom one — not "about 4×," but 4.234 on every one of them (the individual ratios run only from 4.2335 to 4.2341) across MRI, CT, ultrasound, and plain film alike. A ratio that stable across procedures that have nothing physically in common is not a coincidence and it is not ten separate negotiations landing in the same place. It is one base rate table multiplied by a single number. The payer built a base imaging schedule, and the "top" schedule is that base scaled up by 4.23 — the same 4.23 whether you're pricing a $36 X-ray or a $254 brain MRI.

Which means the real variable isn't any single procedure's rate. It is the level of the schedule you land on — and because the schedules are proportional, the distance from the lowest common schedule to the highest is the same 4.23× on every code, from the cheapest X-ray to the priciest MRI.

Mammography is the one code that breaks the pattern, and it breaks it in the direction you'd expect: the top schedule pays 3.90× the bottom instead of 4.23×. Screening mammography is the one imaging service on this list that federal law requires plans to cover at no cost to the patient, and it is the one place the payer pulls its top schedule down toward the rest. The exception is legible precisely because everything else is so rigidly proportional.

Four schedules at or below Medicare, one at triple

Now read the two right-hand columns. The bottom standard schedule pays 0.67× to 0.80× of Medicare — below the government rate on every single code, and only two-thirds of it on X-ray. The three middle schedules (not shown) sit just above that, still landing between roughly two-thirds of Medicare and Medicare itself on every code. Then the top schedule jumps to 2.85× to 3.40× Medicare.

These five rates are the most common, but they are not the whole file: together they cover only about a third of the providers listed on each code. The rest sit on rates in between, which is why the typical provider lands modestly above Medicare — a median of roughly 1.1× to 1.4× across these codes. So this isn't a claim that every provider sits at one of two extremes. It is that the payer's dominant, penny-identical schedules span a 4.23× range on the identical scan, and where a provider falls in that range is set by which schedule it's placed on — not by how hard it negotiated line by line. The "average commercial imaging rate" that anchors most benchmarking blends all of it into one number and hides the schedule underneath.

The multiple against Medicare is not fixed either

Here is the trap for anyone who models commercial imaging as a flat markup over Medicare. The top schedule is a constant 4.23× the bottom schedule — but it is a moving multiple of Medicare: 2.85× on the lumbar X-ray, 3.40× on the brain MRI, 2.90× on the mammogram. The payer's own internal relativities — how it prices an MRI relative to an X-ray — are not the same as Medicare's. So the same top schedule looks like a 2.85× markup on one line and a 3.40× markup on the next.

Both of these are true at the same time, and they are the two facts a finance team has to hold together:

• Between the payer's own schedules, the ratio is fixed. The distance from the bottom schedule to the top is the same 4.23× on every code.
• Against Medicare, the ratio is not fixed. It swings by nearly a full turn depending only on which scan you're pricing.

A rule of thumb like "commercial pays about 3× Medicare for imaging" will overstate what you should be paid on X-ray and mammography and understate it on the high-dollar MRIs — while completely hiding that the payer's most common low schedules pay below Medicare and its top schedule pays roughly triple it.

How to read your own rate

For a provider org or the consultant grading its contracts, the practical lesson is short and a little uncomfortable:

• Your imaging rate is an assignment, not an achievement. When thousands of providers share your exact rate to the penny, you were placed on a schedule, not rewarded for a negotiation. The first question isn't "is my MRI rate good?" It's "which of this payer's schedules am I on, and what does the next one up pay?"
• The prize is a multiplier, not a line item. Because the schedules are proportional, the gap between the bottom schedule and the top is the same multiple on every code — 4.23× in this file. That fixed step, not any single rate, is the size of the conversation worth having.
• Never benchmark against one anchor. "We're at 1.2× Medicare" and "we're at 0.3× the top schedule" can be the same rate. The Medicare comparison tells you how high the market sits off the floor; the schedule comparison tells you where you rank inside a table the payer built. You need both to know which conversation to have — and you need it code by code, because the flat multiple is a fiction on both axes.

None of this required inside information. It is one payer's public transparency file, read against the public Medicare fee schedule, for ten common imaging codes in one city. The prices were always there. The only work was refusing to average them into a single number that hides the schedule underneath.

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Methodology: rates are the negotiated global (undivided professional + technical) amounts for the ten CPT codes shown, drawn from BlueCross BlueShield of Tennessee's in-network home-network machine-readable file for the Nashville area (series 890, vintage 2026-07-27), compared component-for-component (global against global). "Standard schedule" rates are the most frequent negotiated rates on each code — each shared, to the cent, by roughly 1,800–3,600 distinct provider NPIs after expanding the file's provider-reference groups; "bottom" and "top" are the lowest and highest of the five most common. Those five most-common rates together cover roughly a third of the providers listed on each code; the remainder sit on intermediate rates, and the top-to-bottom ratio is a property of the schedules themselves, not of how many providers occupy them. "×Medicare" is the ratio to the 2026 national Medicare Physician Fee Schedule global rate for the code (non-facility total RVU × the 2026 conversion factor of $33.4009, released December 2025). No provider or customer names are used. Every figure is reproducible from the source file and the published fee schedule.