VA Disability Math — 38 CFR 4.25

VA disability ratings don't add up the way you think.

50% + 30% = 65%, not 80%. The VA uses a "whole person" efficiency formula that surprises almost every veteran. Calculate your VA combined disability rating here — then use the result to estimate your VA back pay.

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Calculate Your Combined Rating

Add each rated disability. Check "Bilateral" if it affects a paired extremity (both arms, both legs). Results update instantly.

VA Combined Ratings Calculator

38 CFR 4.25 / 4.26
    Add at least one rating to see results.
    The Whole-Person Concept

    Why the math works this way

    The VA treats you as a whole person with 100% "efficiency." Each disability takes a percentage of whatever efficiency remains — not of the original 100%.

    Think of it like stacking discounts: a 50% rating removes half your efficiency, leaving 50%. A 30% rating then removes 30% of that remaining 50% — which is only 15 points — leaving 35% efficiency. Combined rating = 100% − 35% = 65%, not 80%.

    This is why combined ratings grow smaller the more conditions you add, and why reaching 100% through the schedule is essentially impossible regardless of how many conditions you have.

    The legal source: This formula is codified at 38 CFR § 4.25. VA raters and BVA judges must follow it. Any combined rating that deviates from this formula is an error of law.

    Source: 38 CFR § 4.25 — Combined ratings table

    38 CFR 4.26

    The bilateral factor: a 10% bump you may be missing

    If you have service-connected disabilities affecting paired extremities — both arms, both legs, or a combination of one arm and one leg — you're entitled to a bilateral factor under 38 CFR § 4.26.

    How it works:

    1. Combine all bilateral extremity ratings using the standard efficiency formula.
    2. Add 10% of that combined value to itself (multiply by 1.10).
    3. Then combine the adjusted bilateral value with your remaining non-bilateral ratings.

    Worked example: Left knee 30%, right knee 20%. Combined = 44%. Bilateral adjustment: 44% × 1.10 = 48.4% (rounds to 48%). That 48% now enters the rest of your combined-ratings calculation. Without the bilateral factor you'd use 44% — a 4-point swing that can flip your final rating by 10%.

    The calculator above handles bilateral factor automatically. Check the "Bilateral" box on any extremity disability to include it.

    Source: 38 CFR § 4.26 — Bilateral factor

    3 Real Examples

    Common miscalculations — and the correct VA math

    These three examples show cases where adding ratings would give a completely wrong answer. The VA math consistently produces a lower combined figure than simple addition.

    Ratings Wrong (simple addition) Correct VA math Rounded final
    50% + 30% 80% 65% 70%
    60% + 40% + 20% 120% (capped at 100%) 80.8% → rounds to 80%
    70% + 50% + 30% + 20% 170% (impossible) 87.3% → rounds to 90%

    Notice that 60% + 40% + 20% doesn't reach 100% even though their sum exceeds it. This is deliberate VA policy: the whole-person model means no veteran can reach 100% through ratings accumulation alone regardless of how many conditions they add.

    What to Do With Your Number

    Next steps based on your result

    Your combined rating determines your compensation tier — but it also opens or closes other options.

    Combined hits 70%+?

    You may qualify for TDIU — the 100% compensation rate even without a 100% rating, if disabilities prevent employment.

    → Read the TDIU guide

    Rating feels too low?

    If individual condition ratings are under-assigned, the combined result suffers. Here's how to challenge a denial or low rating.

    → Denied claim guide

    Expecting a new rating?

    Your C&P exam determines individual ratings. Examiner errors are common. Know what to bring and how to push back.

    → C&P exam guide

    Ready to file a claim?

    Once you know your combined rating, file an Intent to File (VA Form 21-0966) to lock your effective date for up to one year while you gather supporting evidence.

    → Intent to File guide →

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    FAQ

    Common questions about VA combined ratings

    Why doesn't 50% + 30% equal 80% for VA ratings?+
    The VA uses a 'whole person' efficiency formula under 38 CFR 4.25. Each rating is applied to the remaining 'whole person,' not simply added. A 50% rating leaves 50% efficiency. A 30% rating then removes 30% of that remaining 50% (15 points), leaving 35% efficiency. Combined = 100% − 35% = 65%, rounded to 70%.
    What is the bilateral factor and when does it apply?+
    Under 38 CFR 4.26, if you have disabilities affecting paired extremities (both arms, both legs), VA adds a 10% bonus on the combined value of those bilateral disabilities before combining with the rest. For example, if your bilateral disabilities combine to 30%, the adjusted value is 30% + 3% = 33%, which then gets combined with your other ratings.
    How does VA round combined ratings?+
    VA rounds the combined percentage to the nearest 10%, with 5% rounding up. So 64% rounds down to 60%, 65% rounds up to 70%, and 75% rounds up to 80%.
    What are the 2026 VA compensation rates for a single veteran with no dependents?+
    2026 VA rates (single veteran, no dependents): 10% = $171.23/mo, 20% = $338.49/mo, 30% = $524.31/mo, 40% = $755.28/mo, 50% = $1,075.16/mo, 60% = $1,361.88/mo, 70% = $1,716.28/mo, 80% = $1,995.01/mo, 90% = $2,241.91/mo, 100% = $3,737.85/mo. Rates are adjusted annually for cost-of-living (COLA).