How RAF Scores Work: Risk Adjustment Factor Scores Explained

What Is a RAF Score?

A Risk Adjustment Factor score, commonly called a RAF score, is a numeric value assigned to each Medicare Advantage beneficiary that predicts how much healthcare that person is expected to need in the coming year. The score is the output of the CMS-HCC risk adjustment model, and it directly determines how much money Medicare pays a health plan to care for that individual.

The concept is straightforward: sicker patients cost more to care for, so plans that enroll sicker patients should receive more funding. The RAF score is how CMS measures "sickness" for payment purposes. A score of 1.0 represents the average expected cost of a community-dwelling Medicare beneficiary. A score of 1.5 means the patient is expected to cost 50% more than average. A score of 0.7 means 30% less than average.

RAF scores vary with the demographics, enrollment status, documented conditions, hierarchy results, and interaction terms in the applicable model. Understanding how those pieces are calculated is essential for any coder working in risk adjustment. For foundational concepts, see our introduction to HCC coding.

Why RAF Scores Matter

RAF scores feed into Medicare Advantage payment, but there is no universal dollar value for a 0.01 change. The payment effect depends on factors outside the raw score, including the county benchmark, plan bid, normalization, and coding intensity adjustment.

This financial significance creates several important dynamics:

Components of a RAF Score

A RAF score has two major components: demographic factors and diagnosis factors.

Demographic Factors

Demographic factors establish a baseline Risk Adjustment Factor score before any diagnoses are considered. These are assigned automatically based on CMS enrollment data, coders do not influence them:

A community-dwelling, non-dual, non-disabled male aged 70 has a V28 community non-dual demographic coefficient of 0.396. This is the starting point before diagnosis coefficients are added.

Diagnosis Factors (Where Coders Come In)

The diagnosis component is where medical coders have direct impact. Each HCC category has a coefficient (weight) that adds to the demographic baseline:

Example calculation:

The example totals 0.922 before interactions and 1.034 after the applicable V28 Diabetes plus Heart Failure interaction is added.

How the RAF Score Calculation Works (Step by Step)

Here is the complete calculation flow from encounter to payment:

The entire calculation happens at the CMS level, coders do not manually compute RAF scores. But understanding the process helps coders recognize which coding decisions have the greatest impact.

V24 vs V28 RAF Weights

During the blend transition period (Payment Year 2024 through 2025), two separate RAF scores were calculated for every patient, one using the V24 model and one using the V28 model, and the final payment used a weighted average. That transition is now complete:

The models differ in their coefficient values, even for HCCs that exist in both. Some notable patterns:

For a comprehensive comparison of what changed, see our V24 vs V28 guide.

Using a RAF Score Calculator

Manually calculating a RAF score requires knowing every demographic coefficient and every HCC coefficient for the relevant model version, plus all applicable interaction terms. This is impractical without a calculator tool.

A good RAF calculator lets you:

HCC Buddy offers a free RAF score calculator that supports both V24 and V28 models, displays individual HCC weights, and handles hierarchy application automatically.

How to Use HCC Buddy's Free RAF Calculator

To use the RAF score calculator:

The calculator handles hierarchy application automatically, if you add both HCC 37 and HCC 38, it removes HCC 38 and shows only HCC 37 in the total, just as CMS would.

Common RAF Score Misconceptions

Several misconceptions about RAF scores persist in the coding community:

"Higher RAF is always better." This is incorrect and potentially dangerous. Deliberately inflating RAF scores through inaccurate coding is healthcare fraud. The goal is an accurate RAF score that reflects the patient's true clinical burden, no more, no less. Plans with artificially inflated RAF scores face Risk Adjustment Data Validation audit exposure, payment clawbacks, and potential fraud investigations.

"RAF scores only matter for Medicare Advantage." While the CMS-HCC model applies to Medicare Advantage, the concept of risk adjustment extends beyond it. The Affordable Care Act marketplace uses a different risk adjustment model (HHS-HCC) that operates on similar principles. Medicaid managed care programs also use risk adjustment models in many states. The skills transfer across programs.

"One missed HCC does not matter much." Every HCC carries real financial weight. The correct V28 CNA coefficient for HCC 37 (Diabetes with Chronic Complications) is 0.166, and that amount is added to the risk score of every qualifying patient for the year. Multiplied across a panel of hundreds of diabetic patients, systematic undercoding of documented complications adds up to meaningful lost risk-adjusted revenue. Every HCC matters.

"RAF scores are permanent." RAF scores are recalculated annually based on diagnoses submitted during the data collection period. Chronic conditions must be re-documented and re-coded every calendar year to continue contributing to the RAF score. A diagnosis coded in 2025 does not carry forward to 2026 automatically, it must appear in a 2026 encounter.

How Coders Impact RAF Scores

Medical coders are the bridge between clinical documentation and RAF scores. Every code you assign either adds or fails to add Risk Adjustment Factor value for a patient:

Understanding documentation requirements is crucial for RAF score accuracy. See our MEAT criteria guide for detailed documentation standards.

For coders who want to see how their code selections translate to Risk Adjustment Factor value, HCC Buddy's encoder displays the Risk Adjustment Factor weight alongside every HCC mapping, giving you immediate visibility into the financial impact of each coding decision.

Conclusion

RAF scores are the financial backbone of risk adjustment, the mechanism through which clinical complexity translates to appropriate plan reimbursement. Understanding how they work makes you a more effective, more valuable medical coder.

The key principles: demographic factors set the baseline, HCC coefficients add diagnosis-based value, hierarchies prevent double-counting, and qualifying combinations add interaction terms. Payment Year 2026 uses V28; V24 remains available for earlier-model review.

Try the free RAF calculator, no signup required for basic calculations. Select your model, enter demographics, add HCCs, and see exactly how each factor contributes to the total score. For full access to all HCC Buddy tools, start Pro.