VA Combined Ratings: Why 30% + 20% Is Not 50%

If you have more than one service-connected disability, the single most common surprise is that the percentages do not add. A 30 percent rating plus a 20 percent rating is not 50 percent. It is 40 percent. This is not a glitch and it is not your rater being stingy. It is the method written into 38 CFR 4.25, and it applies to every claim with two or more ratings.

The whole-person method

VA treats you as starting at 100 percent efficient. Your most severe disability is applied first, and each additional disability is then applied only to the efficiency you have left, not to the original 100.

Walk through 30 plus 20:

1. Start at 100 percent efficient.
2. The 30 percent disability leaves you 70 percent efficient.
3. The 20 percent disability applies to that remaining 70, not to 100. Twenty percent of 70 is 14.
4. Add that 14 to the first 30. The combined value is 44.
5. Round to the nearest 10 percent. A combined value of 44 becomes a 40 percent rating. (A value of 46 would round up to 50.)

VA publishes the result of this arithmetic as the Combined Ratings Table in section 4.25, so raters look the value up rather than recompute it. The table is where you see the classic line that 10 combined with 10 is 19, not 20. The more disabilities you stack, the more pronounced the gap from simple addition becomes, because each new rating works on an ever-smaller slice of remaining efficiency. It is also why reaching a schedular 100 percent through several mid-size ratings is mathematically hard.

Two practical rules fall out of the method:

• Order does not change the final number, but severity order is the convention. Section 4.25 directs that disabilities be arranged in order of severity and combined from the most severe down. The commutative math lands in the same place, but following the order keeps multi-rating cases auditable.
• Rounding happens once, at the very end. Intermediate combined values are kept whole. Only the final figure is rounded to the nearest 10 percent.

You can run any combination on our combined-rating calculator, which is built directly on the section 4.25 table rather than on addition.

The bilateral factor: an extra 10 percent for paired limbs

There is one place VA gives you a built-in boost, and a lot of veterans never claim it because they do not know it exists. It is the bilateral factor in 38 CFR 4.26.

When you have compensable disabilities affecting both arms, both legs, or paired skeletal muscles, VA combines the two paired ratings as usual and then adds 10 percent of that combined value before doing anything else. The regulation is specific: the 10 percent is added, not combined, and it is applied before the result is combined with your other disabilities.

A clean example. Say you have a 10 percent right knee and a 10 percent left knee:

1. Combine the pair: 10 combined with 10 is 19.
2. Apply the bilateral factor: 10 percent of 19 is 1.9. Add it. The pair is now worth 20.9.
3. That 20.9 is treated as a single disability and combined with everything else you have.

The conditions that trigger it must each be compensable, meaning rated at least 10 percent, and they must sit in paired extremities. Section 4.26 also protects you from the factor ever hurting you: if including a disability in the bilateral calculation would somehow produce a lower combined evaluation, VA must remove it and combine it separately, whichever way is most favorable to the veteran. When all four extremities are involved, VA combines the four in order of severity and then adds the 10 percent.

If you have, for example, a rated left and right knee, a left and right ankle, or radiculopathy down both legs, check whether the bilateral factor was actually applied to your award. It is a frequent omission, and it is the kind of arithmetic error a Higher-Level Review is designed to catch, because it is a clear-cut application of the rules rather than a difference of medical opinion.

What the combined number does and does not control

Your combined rating sets your monthly compensation rate and your eligibility for certain thresholds, but the dollar figure also depends on your dependents and on any Special Monthly Compensation you qualify for. The percentage and the payment are two different lookups. To see the current payment at each level, use the VA disability pay tables, and remember that the rate for a given percentage changes with each annual cost-of-living adjustment.

One last point that trips people up: a combined value in the 90s does not automatically become 100 percent. Schedular 100 percent requires the combined value to actually reach it, or a separate route such as a total disability rating based on individual unemployability. The combination math is unforgiving at the top precisely because every additional rating works on a shrinking remainder.