Home › Guides › VA Combined Ratings › 80% + 20%
80% + 20% VA Disability Rating: Combined = 80%
The step-by-step VA math
Why doesn't 80 + 20 = 100?
The VA doesn't add ratings — it combines them under 38 CFR §4.25 ("VA math"). Each additional rating only applies to the part of you the VA still considers non-disabled. That's why combined ratings climb slower and slower as they stack, and why the order (largest first) matters for the calculation but never changes the result.
What if you add a third rating?
Starting from 80% + 20% (table value 84), here is what one more rating would do:
| New third rating | Table value | New combined rating | Change |
|---|---|---|---|
| 10% | 86 | 90% | +10 |
| 20% | 87 | 90% | +10 |
| 30% | 89 | 90% | +10 |
| 40% | 90 | 90% | +10 |
| 50% | 92 | 90% | +10 |
From 80% + 20% (combined value 84), the smallest additional rating that moves you past 80% is a 10% rating — it would take you to 90%. If you think a service-connected condition of yours is unrated or underrated, that is the kind of gap worth documenting properly.
Bilateral factor: paired arms or legs
If your ratings are on paired extremities — both arms, both legs, or an arm/leg pair on opposite sides — the VA adds a 10% bilateral factor to the combined value of those conditions before combining the rest. That can change the final result, so run your full picture through our free calculator, which handles the bilateral factor for you.
Open the free VA disability calculator See all free veteran tools
Have a decision letter you don't agree with, or conditions you never claimed? ASTRID — our AI claims battle buddy — can walk you through next steps in plain language, free to try.