VA Math: Why 50% Plus 30% Isn't 80%

Why regular addition does not work

The VA combines ratings based on how much ability you have left after each disability is counted, not on the raw percentages. It starts with your highest-rated disability, then applies the next rating to whatever ability remains. That is why the numbers do not add straight across.

Here is how it plays out. Say one condition is rated 50 percent. The VA treats you as 50 percent disabled, which leaves 50 percent of your ability intact. Now a second condition is rated 30 percent. That 30 percent applies only to the 50 percent that remains, and 30 percent of 50 is 15. Add that to the first 50 and you reach 65, which the VA rounds to the nearest ten: 70 percent. The official combined ratings table is what sets the exact result.

Where to check your rating

Start with your decision letter. List each service-connected condition and the percentage assigned to it, then find the combined evaluation. Before you decide that number is wrong, remember that it will almost always come out lower than the separate ratings added together on paper.

Rounding is part of the reason. The VA rounds the combined rating to the nearest ten: a value ending in 5 or higher rounds up, and anything below that rounds down. When several smaller ratings are combined, that rounding can pull the final percentage lower than you expected.

One more factor can change the result. If you have disabilities affecting paired body parts, such as both arms or both legs, the bilateral factor may apply and adjust your combined evaluation. When paired limbs are involved, the rating details are worth a closer look.

What to check if the rating feels too low

If the total still feels too low after you account for the combining math, walk through each of these:

• Whether each condition you claimed was granted or denied.
• Whether each condition was rated under the correct diagnostic code, the number the VA uses to match a condition to its rating criteria.
• Whether the symptoms and exam findings on record match the percentage you were assigned.
• Whether the effective date looks right.
• Whether every service-connected condition actually appears on the rating list.

It helps to know which kind of problem you have, because they lead to different reviews. If the combining math is the issue, a review focuses on the listed ratings and the combined table. If a single condition is rated too low for how severe it is, a review focuses on your medical evidence, exam findings, and the rating criteria. Decide which one you are dealing with before you choose a review option.

The most common mistake

The most common mistake is adding the percentages on a calculator, seeing a higher number, and assuming the VA got it wrong. The better first move is to lay your separate ratings, your combined evaluation, and the combined ratings table side by side and compare them. More often than not, the math is correct even when it does not feel that way.