VA Math Explained: Why Your Combined Rating Isn’t What You Expected
- bwelts3
- 3 days ago
- 3 min read
One of the most confusing parts of the VA disability process is the math. You might think that two 30% ratings add up to 60%, right? Not so fast. VA math has its own unique formula—and it’s not just simple addition.
In this blog post, we’ll break down how combined ratings are calculated, why your final percentage might be lower than expected, and how to make sense of the VA’s system.
🧠 The Basics of VA Math
The Department of Veterans Affairs uses what's called a “whole person” approach to determine your combined disability rating. Here's what that means:
The math starts at 100%—the whole person.
Disabilities are subtracted in order of severity, not added.
Each additional rating is taken as a percentage of the remaining “healthy” part of your body.
It may sound complicated (because it kind of is), but let’s walk through it with an example.
🧮 Example: How Two Ratings Combine
Let’s say you have:
A 40% rating for a back condition
A 30% rating for PTSD
Here’s how the VA combines those:
Start with the 40% rating. That means you’re 40% disabled and 60% still “whole.”
Now take 30% of the remaining 60%:
30% of 60 = 18%
Add the 18% to your original 40%:
40 + 18 = 58%
The VA rounds to the nearest 10%.
In this case, you’d be rounded up to a 60% combined rating.
Now let’s throw in a third rating—say 20% for hearing loss:
You’re currently at 60%, which means 40% is still considered “whole.”
20% of 40 = 8%
Add 8% to your previous 58% = 66%, which rounds up to 70%
🔢 The takeaway: The more ratings you have, the smaller impact each additional rating has.
💡 Why Doesn’t It Add Up?
You’re not alone if you’ve done the math and thought, “This doesn’t make sense!”
Here’s why it feels off:
The VA uses descending math, not addition.
Ratings are based on functional loss as a percentage of your total health.
Your highest-rated condition always comes first, which reduces the “whole” each following rating is measured against.
🔄 What About Bilateral Factor?
If you have disabilities on both arms or both legs, the bilateral factor might come into play.
The VA adds an extra 10% of the combined rating for both limbs.
This is before your total is rounded.
👉 For example, if you have 20% in your right knee and 10% in your left ankle, the VA will apply the bilateral factor, then run it through the combined rating formula.
It’s a small boost, but it can make a difference in bumping you up a level.
📊 VA Math Chart
The VA uses a combined rating table to do this math officially. While you don’t need to memorize it, it can be helpful to understand how combinations are rounded.
Combined Rating (Before Rounding) | Final Rounded Rating |
64% | 60% |
65% – 69% | 70% |
74% | 70% |
75% – 79% | 80% |
Every 10% can mean significant benefits—so it’s important to double-check your numbers.
🧾 Tips for Navigating VA Math
1. Always check your award letter.Your decision letter should list all your rated conditions and their percentages.
2. Use a VA disability calculator.There are free tools online that can help you simulate your combined rating using VA math rules.
3. Talk to a professional.If your rating seems wrong or low, a claims expert at United Veteran can walk you through the math—and help file for an increase if needed.
🎯 Final Takeaway
VA math can be frustrating—but understanding how it works puts you in control. If your combined rating isn’t what you expected, it doesn’t necessarily mean a mistake was made—it might just be the way the numbers are calculated.
Still, if something doesn’t feel right, don’t go at it alone.
At United Veteran Benefits Agency, we help Veterans break down the details, understand their ratings, and fight for what they deserve.