38 CFR §4.26
The Bilateral Factor
An extra 10% added when you have ratable disabilities in both arms or both legs — often missed entirely.
Read the official text of 38 CFR §4.26In plain English
When you have service-connected disabilities affecting both arms, both legs, or paired skeletal muscles, the VA recognizes that losing function on both sides is worse than the sum of the two sides taken separately. The bilateral factor is how it accounts for that.
The mechanics: the VA first combines the bilateral disabilities with each other. It then adds 10 percent of that combined value as the bilateral factor. Only after that is the result folded into your overall combined rating and rounded.
The factor applies to paired extremities — not to a back condition, not to conditions on the same side, and not to unpaired organs.
What the rule actually requires
- Applies when there are compensable disabilities of both upper extremities, both lower extremities, or paired skeletal muscles.
- The bilateral disabilities are combined first, then 10 percent of that figure is added.
- The bilateral factor is applied before the rating is combined with other, non-bilateral disabilities.
- Rounding to the nearest 10 percent happens last.
Why this matters to your claim
This is one of the quietest ways a rating comes out low. A veteran with a knee rating on each side may never be told the bilateral factor exists, and the decision letter will not spell it out. It can be the difference between an 80% and a 90% combined rating.
This is our plain-English summary, written for veterans — it is not the regulation itself and it is not legal advice. The controlling text is the current official version, linked above. The VA makes all final decisions about eligibility and payment.
Official text of 38 CFR §4.26