VA Math Does Not Just Add Your Two Knee Ratings Together

Veterans with two bad knees usually assume the VA just runs both ratings through the same combined ratings table as everything else. Close, but there's a step in between that a lot of people never hear about.

When both knees are service connected, the VA rates each one separately first, based on its own symptoms — painful motion, limited flexion, instability, whatever applies to that knee. So far, that part matches what most veterans expect.

Here's the part that doesn't. Because both knees are paired extremities, the VA applies something called the bilateral factor under 38 CFR § 4.26. It combines your two knee ratings together like normal, then adds an extra 10% on top of that specific combined value, before that number ever gets folded in with the rest of your body.

That extra 10% isn't 10 percentage points tacked onto your final number. It's 10% of the combined value of just the two knees, calculated the same way VA math combines everything else. It sounds small written out like that, but on a decision letter it usually shows up as its own separate line, and veterans regularly skip right past it thinking it's a clerical note instead of money.

This isn't unique to knees. Same rule applies to any paired body parts — both arms, both hands, both feet, paired muscle groups, even paired sensory organs like hearing in both ears when applicable.

If you're self-checking your combined rating with your two knee percentages and a calculator, and the number doesn't match your decision letter, this is usually why. You're missing a step the VA doesn't advertise clearly anywhere in plain language.

The bottom line is this: two service-connected knees aren't rated in isolation from each other. Look for the bilateral factor line on your own decision letter — if both your knees are rated and you don't see it, that's worth asking your VSO about directly.

Are both of your knees service connected? Did you know about the bilateral factor before this?