Why Don’t My VA Disability Ratings Add Up? Understanding VA Math

If you have more than one service-connected medical condition, you may be unsure how the VA came up with your combined disability rating. VA math can be confusing if you aren’t familiar with the formula for VA disability ratings. For example, if you’re rated 40% disabled due to one condition and 30% due to another, you might logically expect that your combined disability rating would be 70%. Instead, it’s 60%. But where do those numbers come from? Our experts are ready to break down VA Math for you now!

The Basis for VA Math

The concept behind VA math is simple: a person can’t be more than totally disabled. If the VA simply combined disability ratings through addition, many veterans would have VA disability ratings exceeding 100%. For example, a veteran with a 70% rating for one condition and a 50% rating for another condition would be rated 120% disabled. The VA’s formula avoids that.

You won’t have to pull out your calculator to figure out your combined VA disability rating. There’s a table in the Code of Federal Regulations (CFR). But even the table can be confusing if you don’t understand how VA math works. Here’s a section of the table. 

VA Math explained:

At first glance, the table may raise more questions than it answers: 

• Why do the ratings on the left start at 19 instead of 10? 
• Why do the ratings along the left go up one by one when all VA disability ratings are assigned in increments of 10? 
• Why aren’t the combined ratings in increments of 10? 
• Why do some of the combined ratings stay the same line after line? 

To answer those questions, you’ll need a basic understanding of the math behind combined ratings. 

Calculating Combined VA Disability Ratings

The CFR also explains the math step by step. 

1. Start with the condition assigned the highest VA disability rating
2. Subtract that rating from 100 to determine the remaining percentage of functionality (called efficiency in the CFR)
3. Multiply the next-highest disability rating by the result
4. Add the answer to the original disability rating
5. Repeat for any additional ratings
6. Round to the nearest 10%

Let’s start with a simple example involving just two rated conditions. Say the first condition is rated at 60% and the second at 20%. Following the steps above, you’ll start with 60% and subtract it from 100.

100% – 60% = 40% (1 – .60 = .40)

40% is your remaining “efficiency.” You’ll take that remainder and multiply it by the 20% rating for the second condition. 

.40 x .20 = .08

The result is 8%. You’ll combine the ratings by adding that 8% to the original 60% rating, for a total of 68%. That would also be the result if you followed the table down the left-hand column to 60% and then across to 20%.

However, your VA disability rating isn’t 68%. All VA disability ratings are in increments of 10. You’ll round to the nearest 10 for a combined disability rating of 70%. 

What if You Have Three or More Disability Ratings? 

If you have additional disability ratings, you’ll repeat the process, using the unrounded result above as the starting disability rating. That’s why you have increments of one in the left-hand column. The first rating in that column, 19%, is the combination of two 10% disability ratings. 

For simplicity, let’s assume the first two ratings were the same as those in the example above. However, you also have a third service-connected condition that is rated at 10%. 

After your calculations, but before rounding, you have a combined rating of 68%. Use that number and walk through the steps again.

100% – 68% = 32%

.32 x .10 = .032 (3.2%)

68% + 3.2% = 71.3%

Round your final result (71.3%) to the nearest 10 for a disability rating of 70%. So, the three disability ratings (60%, 20% and 10%) add to 90%, but result in a combined disability rating of 70%. 

This process continues for as long as there are additional disability ratings to factor in–just remember not to round until after the last calculation. The impact gets smaller and smaller with each calculation, because there is a smaller percentage of efficiency left to work with.

Imagine, for example, that there’s a fourth rating in the example above. Here’s how the additional calculation would play out.

100% – 71% = 29%

.29 x .10 = .029 (2.9%)

71.3% + 2.9% = 74.2%

Like 71.3%, 74.2% rounds to 70%. So, the additional 10% rating did not increase the veteran’s overall VA disability rating. 

VA Math Comes Second in Calculating Disability Ratings

Understanding VA math can help you know what to expect when your VA disability ratings are combined and what it will take to move the needle and bump you to the next disability rating. But it’s important to remember that the foundation of that math is the VA disability ratings assigned for each individual condition. 

Those individual ratings depend on the medical evidence you provide to the VA and the outcome of any C&P exams or testing the VA sends you for. You can’t change the way VA math works, but you can maximize your VA disability rating by ensuring that you are providing sufficient medical documentation to support the highest appropriate disability rating for each condition. 

Whether you are just preparing to file your VA disability claim or you have received a disability rating and believe it is too low, Veterans Help Group is here for you. Our seasoned VA disability benefits advocates understand what’s required to submit the strongest possible claim or appeal. To learn more about how we can help, call 855-855-8992 right now, or fill out our contact form HERE.

FAQ: VA Math, Disability Ratings and Combined Ratings

Why don’t my VA disability ratings add up to what I expected? The VA doesn’t add ratings together. It uses a formula based on remaining functional capacity. Each additional rating is applied to what’s left after the previous one, not to 100%. A 60% rating and a 20% rating combine to 68%, which rounds to 70%, not 80%.

What is “VA math”? VA math is the combined ratings formula the VA uses to calculate a veteran’s overall disability rating when more than one condition is service-connected. The formula prevents total ratings from exceeding 100% by applying each successive rating to the remaining efficiency, not to the whole.

How does the VA calculate combined disability ratings? Start with the highest individual rating. Subtract it from 100 to find the remaining efficiency. Multiply the next rating by that remainder. Add the result to the first rating. Repeat for each additional rating. Round only at the end, to the nearest 10%.

Why does my combined VA disability rating stay the same even when I add another condition? Once your unrounded combined rating is high enough, adding a low-percentage condition may not move the final number past the next rounding threshold. For example, adding a second 10% rating to a combined 71.3% yields 74.2%, which still rounds to 70%.

How can I increase my VA disability rating? The math itself doesn’t change, but the individual ratings that feed into it can. Each condition’s rating depends on the medical evidence you submit and the results of any C&P exams. A stronger claim with thorough documentation supports a higher rating for each condition, which raises the combined result.

Disabled Veteran Resources:

• FREE Downloadable VA Disability Benefit Guidebooks
• Veteran Social Security Disability Qualification Questionnaire
• Most Commonly Approved VA Disability Claims
• Veterans Disability Benefits Calculator