Unveiling the Primary Care Payer-Spread Index: How to Unlock Millions in Hidden Outpatient Revenue

Discover how a simple ratio can expose an average ~46% price gap on common primary care services, and learn how your health system can turn transparency into profit. 

For a large health system with an extensive primary care footprint—say, 300 physicians delivering around 1.2 million visits annually—if our six target visit codes account for roughly half of those encounters (~600,000 visits), and the average PSI across four markets indicates a 46% pricing gap (~1.46×), the potential upside is significant. By aligning your lowest-paid contracts with your highest benchmarks, the estimated annual revenue uplift exceeds $40 million (600,000 visits × average reimbursement × 46%). This illustrates the substantial revenue hidden in plain sight due to primary care pricing disparities.

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Hidden Gaps in Plain Sight

Commercial payer contracts for physician services have long been shrouded in confidentiality. Clinics and health systems only saw their own negotiated rates; payers saw only theirs. Now, thanks to the federal price-transparency rule, those secret agreements are exposed, revealing that insurers often pay dozens of percent more for the same office visit at the same clinic. 

Our analysis of primary care pricing across multiple markets finds an average ~46% gap between the highest and lowest reimbursements for identical outpatient visit codes. In other words, one insurer might be paying nearly one and a half times what another is paying for the exact same primary care visit, with the same doctor, at the same location. These gaps vary by market, but they are pervasive—and they represent revenue that many health systems are leaving on the table today.

Introducing the Payer-Spread Index

We distilled these disparities into one clear metric for primary care services:

PSI = (Highest negotiated commercial rate) ÷ (Lowest negotiated commercial rate) for the same outpatient visit (CPT code) at the same practice or system.

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This “Payer-Spread Index” (PSI) lets you quantify payer spread at a glance:

• PSI = 1.0× → perfect parity (all payers reimbursing equally)
• PSI ~ 1.46× → average four-market spread in our primary care analysis (≈46% gap)
• PSI > 2.0× → one payer pays twice what another pays for the same visit

In our previous hospital inpatient analysis, the average PSI was about 1.48× (48% gap) – and now we see similarly stark inequities in the outpatient setting (~1.46×). Even though office visits have lower dollar amounts than DRGs, the relative spread between highest and lowest payer is almost as wide. A PSI above 2.0× in primary care is not theoretical; it means one insurer is literally reimbursing a provider 100% more than another insurer for the same appointment, a situation now visible and actionable thanks to transparency.

How We Measured It

Using Trek Health’s Pricing Transparency platform, we analyzed newly published insurer rate data (machine-readable files) for commercial payers in Chicago, Los Angeles, New York, and Atlanta. We focused on six high-impact primary care billing codes often used for office visits:

• New patient office visits: CPT 99202–99205 (ranging from minor to complex new patient evaluations)
• Established patient visit: CPT 99213 (mid-level follow-up visit, a common encounter)
• Preventive adult exam: CPT 99395 (routine annual physical exam for adult patients)
  
  

For each city and each service code, the platform pulled every insurer’s negotiated rate (using data filtered to primary care providers) and computed the ratio of highest-to-lowest reimbursement for that exact service at the same provider. In other words, for each clinic–CPT pairing we found the top-paying payer versus the bottom-paying payer and calculated the PSI. We then aggregated these findings to see overall patterns by market. (All rates analyzed are negotiated in-network commercial rates, as reported under the transparency rule.)

What We Found: Market Snapshots

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Across the four metropolitan areas, primary care PSI values varied, but none was immune to significant spreads. Here are the average PSI results by market, and some notable insights:

• Chicago – PSI ~1.3× (+30% spread above lowest rate): A relatively tight range. Most common office services see only about a 20–30% reimbursement difference among major payers, indicating more uniform contracting in this market.
• Los Angeles – PSI ~1.6× (+60% spread): The largest disparities of the four markets. Certain primary care services—for example, adult preventive exams—showed payer spreads approaching 2× (one insurer paying nearly 100% more than another). Los Angeles payers appear highly variable in what they’ll pay for the same visit.
• New York – PSI ~1.45× (+45% spread): Several of the dominant New York payers cluster fairly close (within ~10% of each other on many codes), but outliers exist. We observed a few extreme contract outliers where a particular payer’s rate was several times the lowest rate for a given service. (In one case, an out-of-network or ancillary rate made an insurer’s payment look almost 4× higher than the norm, a dramatic spread.) Overall, mid-pack payers in NYC are closer together, but the PSI still averages ~1.45× due to those anomalies.
• Atlanta – PSI ~1.5× (+50% spread): Payer spreads in Atlanta hovered around the 50% mark on average. It was common to find one payer reimbursing about one-and-a-half times what another paid for the same office visit. The variation was fairly consistent across the board; no single visit type dominated the spread – meaning there is broad opportunity in Atlanta to bring low-end contracts up toward the top. (In our inpatient analysis, Atlanta had a 53% spread on average, and we’re seeing a very similar story in primary care.)

Overall four-market average: PSI ≈ 1.46×, meaning about a 46% gap between highest and lowest commercial payments for identical primary care visits. In plain language, a clinic’s worst-paying insurer might be paying only $70 for a visit that another insurer pays $100+ for in the same city—a huge hidden margin.

Why It Matters

These hidden spreads represent very real, recurring revenue for provider organizations. A few key takeaways:

• Strategic uplift: Closing a ~46% payment gap on thousands of visits can add tens of millions of dollars to annual revenue. For example, as illustrated earlier, aligning the lowest contracts to match the highest for ~600k primary care visits could net on the order of $40 million per year in additional revenue. In smaller practices or specific service lines, the absolute dollars will vary, but the percentage gain (30–60% more per visit) goes straight to your bottom line.
• Negotiation leverage: You now have hard data to negotiate more equitable rates. It’s a powerful message when you can tell a payer, “Insurer X is paying 40% less than Insurer Y for the same 99203 office visit—that needs to change.”
• Transparency turns previously secret rate disparities into actionable leverage at the bargaining table.
• Focused action: The PSI analysis highlights which payers and which CPT codes have the biggest spreads, so you can target them first. Maybe it’s a certain insurer consistently underpaying on new patient visits, or perhaps preventive exams with one health plan are way below market. By pinpointing the highest-PSI services and payers, your next contract cycle can focus on closing those specific gaps for maximum impact.

In short, the Payer-Spread Index turns pricing transparency data into a roadmap for revenue recovery. Every percentage point you close in a spread is money back to your practice or health system—for the same services you’re already providing.

Take Action with Trek Health

Transparency isn’t just about compliance, it’s a competitive edge. Leveraging Trek Health’s platform, health systems and medical groups can transform opaque rate files into actionable intelligence. Are you ready to:

1. Calculate your organization’s Payer-Spread Index, and see where your biggest payer gaps are
2. Benchmark your rates against peers and market norms
3. Negotiate more equitable, profitable contracts that lift your lowest reimbursements closer to the top

Connect with the Trek Health team to get started. Harness the power of transparency to drive smarter payer negotiations and maximize your outpatient revenue. The dollars are on the table, a clear view of your PSI can help you grab them.

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