Updated July 2026

VA Bilateral Factor Calculator — Does Your Combination Qualify?

The bilateral factor applies when you have compensable (10%+) ratings on both arms, both legs, or paired skeletal muscles — including mismatched combos like a left knee and a right hip (both lower extremities). One arm plus one leg does not qualify. When it applies, the VA combines the paired ratings and adds 10% of that combined value (not 10 percentage points) under 38 CFR § 4.26. Pick your rated body parts below to get a YES, NO, or IT DEPENDS — with the math shown.

Check Your Combination

Add each service-connected condition, pick the body part it affects, and select its rating. Include 0% ratings — they matter for the both-sides-compensable rule.

Your Results

Bilateral Factor

Per 38 CFR 4.26

Payable Rating

Combined & rounded

Est. Monthly Pay

Veteran alone, 2026

The Math, Step by Step

Note: Monthly figures shown here use the 2026 veteran-alone rate. Dependent additions apply at 30%+ — use the VA Disability Rating Calculator for your full payment.

How the Bilateral Factor Works (38 CFR § 4.26)

When compensable disabilities affect both arms, both legs, or paired skeletal muscles, the rater combines the left- and right-side ratings as usual under the combined ratings table (38 CFR § 4.25), then adds — not combines — 10 percent of that value. The result is rounded to the nearest whole number and treated as one disability when it's combined with everything else you're rated for. The logic: losing function on both sides of the body is more disabling than the two ratings suggest in isolation.

Worked example: right knee 30% + left knee 20%

Step 1: Combine the pair under § 4.25: 30 + (20% of the remaining 70) = 30 + 14 = 44.

Step 2: Add 10% of that value: 44 + 4.4 = 48.4, rounded to 48.

Step 3: If these are your only ratings, 48 rounds to a 50% payable rating. Without the factor, 44 would round to 40%.

What it's worth in 2026 (veteran alone): $1,132.90/month at 50% vs. $795.84/month at 40% — the bilateral factor is worth $337.06/month ($4,044.72/year) in this example.

The regulation's own example shows the same mechanics with more ratings: a veteran rated 60%, 20%, 10%, and 10%, where the two 10s are a bilateral pair — the 10s combine to 19, the factor adds 1.9 for 21, and the ratings are re-ranked as 60, 21, 20, combining to 68, then 74, which converts to a 70% combined rating.

What Qualifies — and What Doesn't

Qualifies: compensable (10%+) ratings on both upper extremities or both lower extremities — any location, any condition type. The conditions don't have to match: a left knee and a right hip qualify (both lower extremities). The regulation's own example pairs a right thigh amputation with left-foot pes planus.
All four extremities: if both arms and both legs are affected, all four ratings are combined in order of severity and a single 10% factor is added to that one value (§ 4.26(b)) — not two separate factors.
Does not qualify: one arm plus one leg (not "paired extremities"); a pair where one side is rated 0% (each side must be compensable, § 4.26(c)); non-extremity conditions like the back, PTSD, or tinnitus; and paired organs (eyes, ears, kidneys, lungs) — those fall under a separate rule (38 U.S.C. § 1160 / 38 CFR § 3.383), not the bilateral factor.

Edge Cases Veterans Ask About

Two conditions on the same leg (or arm)

A left knee and a left ankle don't pair with each other — the factor requires both sides. But both count as left-lower-extremity disabilities, so if you also have any compensable rating on your right leg (any condition — hip, knee, ankle, foot, or radiculopathy), all of your lower-extremity ratings join one bilateral group together, and the 10% factor is applied to their combined value.

One side rated 0% (non-compensable)

Each side of the pair must carry a compensable rating — 10% or higher (§ 4.26(c)). A 30% left knee with a service-connected but 0% right knee does not get the factor. If the 0% side is later increased to 10% or more, the pair qualifies from that point.

Radiculopathy from a back or neck condition

Your spine rating itself never joins a bilateral group — the back is not an extremity. But radiculopathy is rated separately as impairment of the affected limb. Compensable radiculopathy ratings in both legs (or both arms) form a bilateral pair and get the factor, even though they stem from a single spine condition.

Both eyes, both ears, both kidneys, both lungs

Paired organs are handled by a different rule — 38 U.S.C. § 1160, implemented at 38 CFR § 3.383 — not the bilateral factor. The bilateral factor in § 4.26 covers extremities and paired skeletal muscles only. See the official sources or ask a VSO about how paired-organ conditions are compensated.

Can the bilateral factor ever lower my rating?

Not anymore. Effective April 16, 2023, 38 CFR § 4.26(d) (added by 88 FR 22917, published April 14, 2023) requires the VA to exclude one or more bilateral disabilities from the bilateral-factor calculation whenever including them would produce a lower combined evaluation — whichever computation is most favorable to you controls. Older articles warning that the factor can occasionally work against you are out of date.

Is it automatic, or do I have to ask for it?

It's automatic — when the criteria are met, § 4.26 directs the rater to apply the factor, and you don't file anything extra. That said, the factor is easy to miss in a busy decision, so it's worth re-running the math on your rating decision (this tool or our full calculator will do it). If the factor was skipped, a VSO can help you raise it.

Frequently Asked Questions

Do both knees count toward the VA bilateral factor?

Yes. Both knees are disabilities of both legs, so compensable (10% or higher) ratings on each knee qualify under 38 CFR 4.26. The VA combines the two knee ratings first, then adds 10% of that combined value.

For example, a 30% right knee and a 20% left knee combine to 44; the factor adds 4.4 for a bilateral subtotal of 48.

Does a left knee plus a right hip count as bilateral?

Yes. The conditions do not have to match — a left knee condition and a right hip condition both affect the lower extremities, so they qualify as a bilateral pair.

The regulation's own example pairs a right thigh amputation with left-foot pes planus.

Does one arm and one leg qualify for the bilateral factor?

No. The bilateral factor requires paired extremities — both arms or both legs (or paired skeletal muscles). One upper extremity plus one lower extremity does not qualify, no matter which sides are affected.

Is the bilateral factor automatic, or do I have to request it?

It is automatic. When compensable ratings affect both arms, both legs, or paired skeletal muscles, 38 CFR 4.26 directs the rater to apply the factor — you do not file a separate request.

It is still worth checking the math in your rating decision, because the factor is easy to miss.

How much does the bilateral factor add?

It adds 10 percent of the combined value of the paired ratings — not a flat 10 points. Two knees at 30% and 20% combine to 44; the factor adds 4.4 for 48.

If those are your only ratings, that is the difference between a 40% payable rating ($795.84/month in 2026, veteran alone) and 50% ($1,132.90/month) — $337.06 more per month.

Data Sources

Every figure here comes from the official sources below. See our full methodology for how we source and verify each rate.

38 CFR § 4.26 — Bilateral Factor (amended by 88 FR 22917, effective April 16, 2023)
38 CFR § 4.25 — Combined Ratings Table
2026 VA Disability Compensation Rates

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