VA combined rating calculator: how VA math works
The VA does not add your ratings. It stacks them against whatever efficiency is left, which is why the fourth condition is worth less than the first, and why the combined rating can come out lower than the sum of the individual ratings.
VA combines disability ratings with its Combined Ratings Table instead of adding them. For example, 50% and 30% combine to 65, which converts to 70% if no other ratings apply. You can estimate your own result with the combined rating calculator, which takes each individual rating and marks paired-limb ratings for the bilateral factor; VA decides your official rating (38 CFR § 4.25).
So a veteran with a 50% rating and a 30% rating does not have an 80% combined rating. They have 70%. Nothing was taken from them and no one made a mistake. That is simply how 38 CFR § 4.25 works.
Understanding the arithmetic explains why a fourth 10% rating may not move the final number at all (and when it does), and where the jumps between combined ratings actually sit.
The whole-person model
The VA treats you as starting at 100% efficient. Each disability takes a percentage of what remains, not a percentage of the original hundred.
So a 50% rating leaves you 50% efficient. The next rating, 30%, is applied to that remaining 50, not to the full 100:
| Step | Calculation | Running total | Efficiency left |
|---|---|---|---|
| Start | — | 0% | 100% |
| Apply 50% | 50% of 100 = 50 | 50% | 50% |
| Apply 30% | 30% of 50 = 15 | 65% | 35% |
65 is the combined value. That whole number is what the VA's combined ratings table holds at this step, and it is what gets carried into the next combination. Only after every rating has been combined does the VA round the final value to the nearest 10: 65 rounds up to 70%.
Order your ratings highest to lowest, then repeatedly: take the next rating's percentage of the efficiency left, add it to the running total, and round that total to a whole number. The efficiency left for the next step is 100 minus that new total. Round to the nearest 10 once, at the very end. The whole-number step is how the VA's table works, and skipping it can occasionally put you on the other side of a rounding line from VA's result.
A three-condition example
Say you are rated 50% for a mental health condition, 30% for migraines, and 20% for a back condition.
| Rating | Applied to | Adds | Running total | Efficiency left |
|---|---|---|---|---|
| 50% | 100 | 50 | 50 | 50 |
| 30% | 50 | 15 | 65 | 35 |
| 20% | 35 | 7 | 72 | 28 |
Combined value 72 → rounds down to 70%. Note what happened: the 20% rating added seven points and did not move the final number at all. If instead the third condition had been rated 30%, it would have added 10.5 points, which the table holds as 76, and 76 → 80%. The gap between a 20% and a 30% rating on that third condition is an entire 10-point step in compensation.
Why the order is highest-first
Because every step is rounded to a whole number, the order you combine in can change the result by a point, and a point is sometimes the difference between rounding down and rounding up. That is why the regulation does not leave the order to you: 38 CFR 4.25 says the disabilities are arranged in the exact order of their severity, highest first, and the READY214 calculator sorts them that way before it starts. Follow the same order by hand and you should reach the same combined value VA's table gives.
The bilateral factor
If you have disabilities affecting paired extremities, both arms, both legs, or paired skeletal muscles, 38 CFR § 4.26 adds a bonus. The bilateral conditions are combined with each other first, then 10% of that combined value is added, and only then is the result combined with everything else.
The factor applies only when each side of the pair carries a compensable rating, under § 4.26(c). Since April 2023, § 4.26(d) also takes a bilateral rating out of the bilateral-factor step and combines it separately whenever doing so produces a higher combined evaluation, so the factor can no longer lower a result.
Example: 20% right knee, 10% left knee, 30% for an unrelated condition.
| Step | Calculation | Value |
|---|---|---|
| Combine the bilateral pair | 20, then 10% of the remaining 80 = 8 | 28 |
| Add the bilateral factor | 10% of 28 = 2.8, so 30.8, carried as a whole number (§ 4.26's own example turns two bilateral 10s, which combine to 19, into 21) | 31 |
| Combine with the 30% | 31 first (it is the larger), then 30% of the remaining 69 = 20.7, so 51.7, which the table holds as | 52 |
| Round | nearest 10 | 50% |
Without the bilateral factor the same conditions combine to 50 (30, then 44, then 49.6 held as 50), which also rounds to 50, a reminder that the factor helps at some values and disappears into rounding at others. It matters most when you are sitting near a boundary.
Why the last 10% is so hard
Look at what each additional 10% rating is worth as your combined value climbs:
| Already at | A new 10% rating adds |
|---|---|
| 0% | 10.0 points |
| 50% | 5.0 points |
| 70% | 3.0 points |
| 90% | 1.0 point |
From a combined value of 90, three separate 10% grants move it only to 93 on Table I (91, then 92, then 93), which still converts to 90%. Reaching 95, the value that converts to 100%, takes five new 10% ratings (91, 92, 93, 94, 95) or fewer, larger ones, such as a single new 50%. Small ratings can get there, but each one adds only about a point.
The route to being paid at the 100% rate may not be another small rating. It is either an increase on a condition that is already rated but under-rated, or Total Disability based on Individual Unemployability, which pays at the 100% rate without a 100% schedular rating. See the TDIU guide.
Rounding: the last step, and only the last step
Two rules that trip people up:
- Round once. The intermediate values are carried as the whole numbers Table I shows, never rounded to the nearest 10. If you round to the nearest 10 after each combination you will drift away from the VA's number.
- Round to the nearest 10, with 5 going up. 64 → 60. 65 → 70. 74 → 70. 75 → 80.
Suppose a veteran is rated 30% for one condition and 20% for each of two others, none of them affecting paired limbs or muscles, so § 4.26 does not apply. Under § 4.25 the ratings are arranged 30, 20, 20 and combined in that order.
- Start at 30. That leaves 70% efficiency.
- Combine the first 20%: 20% of the remaining 70 is 14, for a combined value of 44. Table I shows 44 where the 30 row meets the 20 column.
- Combine the second 20%: 20% of the remaining 56 is 11.2, or 55.2. Table I shows 55 where the 44 row meets the 20 column.
- Convert once: 55 ends in 5, so it is adjusted upward to 60%.
Had the 44 been rounded to 40 after step 2, Table I would combine 40 and 20 as 52, which converts down to 50%. One early rounding moves the same three ratings a full 10-point step, which is why § 4.25(b) allows the conversion to a multiple of 10 only once per rating decision, after every disability has been combined.
This is why the exact combined value matters even though your award letter shows a round number. Sitting at 74, a single new 10% rating combines to 77 and converts to 80%; sitting at 71, the same 10% rating combines to 74 and converts to 70%.
What the combined rating does and does not decide
The combined percentage sets your basic monthly compensation rate, and dependents (spouse, children, dependent parents) increase that rate at 30% and above. But several things run on their own rules and are decided separately:
- Special Monthly Compensation is paid for specific losses at its own rates under 38 U.S.C. § 1114, not derived from the combined percentage: the (k) award is paid on top of the regular rate, while the (l) through (o) levels are standalone rates.
- TDIU pays at the 100% rate based on employability, with its own percentage thresholds under § 4.16.
- Permanent and Total status affects future exams and dependent benefits, and is a separate determination from reaching 100%.
- Ancillary benefits, healthcare priority, state benefits, property tax exemptions, commissary access, each have their own thresholds, and several state benefits key off 100% or P&T specifically.
A note on pyramiding
You cannot be rated twice for the same symptom under two different diagnostic codes, § 4.14 prohibits it. What you can do is claim genuinely distinct manifestations separately: a back condition rated on limitation of motion and a separate radiculopathy rated on the nerve, for example, are different disabilities with different criteria. Knowing the difference helps you claim each distinct problem without claiming the same one twice.
Combined rating questions
Where can I calculate my VA combined rating?
Use the READY214 combined rating calculator. Enter each individual rating, mark the ones that affect paired arms, legs or skeletal muscles so the bilateral factor is applied, and it shows each step of the combination and the rounded result. It estimates only; it cannot tell you whether a condition will be service connected, and VA decides the official rating. VA's own table is on VA.gov.
Why do VA disability ratings not add up?
VA treats each rating as taking a share of the efficiency left after the ratings before it, highest first. A 50% rating leaves 50% efficiency; a 30% rating then takes 30% of that 50, or 15, for a combined value of 65. With no other ratings, 65 converts to 70%. The Combined Ratings Table, Table I, does this arithmetic for every pair (38 CFR § 4.25).
How does the VA bilateral factor work?
When both arms, both legs, or paired skeletal muscles each have a compensable rating, VA combines those ratings first, then adds, not combines, 10% of that combined value, and combines the result with your other ratings in order of severity. Under 38 CFR § 4.26(d), added in 2023, if leaving a bilateral rating out of that step would give a higher combined evaluation, VA leaves it out, so the factor cannot lower your result (38 CFR § 4.26).
How does VA round combined ratings?
Each step carries the whole-number combined value Table I shows, such as 65 or 72, into the next combination. Conversion to the nearest 10 happens only once per rating decision, after every rating is combined, and values ending in 5 go up: 64 becomes 60, 65 becomes 70. That is why the exact combined value matters even though your letter shows a rounded rating (38 CFR § 4.25(a), (b)).
Sources
- 38 CFR § 4.25, Combined ratings table: arranging ratings by severity, Table I, carrying each combined value exactly as the table shows it, and converting to the nearest 10 only once, with 5s adjusted upward.
- 38 CFR § 4.26, Bilateral factor: which paired extremities and muscles qualify, adding (not combining) 10% of the bilateral value, the compensable-rating requirement, and the paragraph (d) exception.
- Exceptions to Applying the Bilateral Factor in VA Disability Calculations, 88 FR 22914 (Apr. 14, 2023): the interim final rule, effective April 16, 2023, that added the exception, later adopted as final without change.
- 38 CFR § 4.14, Avoidance of pyramiding: bars rating the same manifestation under different diagnoses.
- 38 CFR § 4.71a, General Rating Formula for Diseases and Injuries of the Spine, Note (1): associated objective neurologic abnormalities are evaluated separately under their own diagnostic code.
- 38 U.S.C. § 1115, Additional compensation for dependents: dependent amounts start at a rating of 30% or more.
- 38 U.S.C. § 1114, Rates of wartime disability compensation: the schedular rates and the separate Special Monthly Compensation rates in subsections (k) onward.
- VA.gov, About VA disability ratings: VA's own step-by-step use of the combined ratings table, including carrying each combined value, before rounding to the nearest 10, into the next step.
READY214 has a free combined-rating calculator with the bilateral factor built in, plus a condition library showing what each rating level actually requires. No account needed.