VA Math Explained — Combined Ratings & Bilateral Factor
The whole-person concept
VA starts with a 100% 'efficient' person. Your highest rating is subtracted from 100 to give the remaining 'efficiency.' The next rating is applied to that remainder — not the original 100. Each successive rating chips away at a smaller and smaller piece.
Worked example: 50% + 30%. After the 50%, you have 50% efficiency left. The 30% takes 30% of that 50, or 15. Add it back: 50 + 15 = 65, rounded to 65, then to the nearest 10 → 70%.
Why the order doesn't matter
Combine them in any order and you get the same answer, because multiplication is commutative. But because each new rating is applied to a smaller remainder, adding a 10% rating to a already at 90% only moves them to 91% — which rounds back down to 90%. This is why low-percentage add-ons rarely change the .
The bilateral factor (38 CFR § 4.26)
When a has compensable ratings on both arms, both legs, or paired skeletal structures (e.g., both knees), VA adds a 10% bonus to the combined value of those paired ratings before combining them with the rest of the body.
Example: 20% right knee + 20% left knee. Combine them: 20 + 16 = 36. Add 10% of 36 = 3.6, rounded → 4. New paired total: 40. Combine 40 with the rest of the body using the standard table.
The 10-point rounding rule
After every combination is complete, the final number is rounded to the nearest 10. 74 rounds to 70; 75 rounds to 80. This single rule has more impact on monthly compensation than any other math step — moving from a combined 84 to a combined 85 jumps the rating from 80% to 90%, a difference of nearly $700/month.
Practical implications for claim strategy
- Once you are at 80% or 90%, low-percentage add-ons (10%, 20%) almost never move the . Pursue 30%+ ratings or .
- The makes paired claims (both knees, both ankles, bilateral radiculopathy) disproportionately valuable.
- Crossing a rounding threshold — going from 84 to 85 — is the single highest-yield outcome.
- Reaching combined 100% via the schedule unlocks ancillary benefits does not unlock the same way ( stacking).
Where these claims break down
- ×Adding ratings arithmetically (50 + 30 = 80) and being shocked when the award letter says 70%.
- ×Pursuing low-percentage secondaries while already at 80%+ without checking whether they actually move the combined rating.
- ×Overlooking the bilateral factor on paired conditions.
- ×Forgetting that rounding happens once, at the very end — not at each step.
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Disclaimer: This page is for educational purposes only and does not constitute legal advice. Oakridge Claims is a private business and is not affiliated with, endorsed by, or operated by the U.S. Department of Veterans Affairs. No guarantees of outcomes are made. Each claim is decided on its individual facts.
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