If you’ve ever looked at your VA disability ratings and thought, “70% + 50% + 50% should be way over 100%,” you’re not alone.
But that’s not how the Department of Veterans Affairs calculates disability compensation.
Instead of simple addition, the VA uses a unique formula often called VA Math to determine your combined disability rating. This system focuses on how much of your body is still considered “efficient” after each disability is applied.
Understanding VA Math is critical because your combined rating directly affects how much monthly compensation you receive, whether you qualify for dependents’ pay, and even eligibility for benefits like TDIU or Special Monthly Compensation.
Let’s break it down step by step in plain English.
What Is VA Math and Why Does the VA Use It?
VA Math is the method the Department of Veterans Affairs uses to combine multiple service-connected disabilities into one final rating.
Instead of adding percentages together, the VA assumes:
- You start 100% healthy
- Each disability reduces what remains
- Every new condition affects only the remaining efficiency
“VA Math exists to reflect real-world functional loss, not simple arithmetic,” explained by VA disability expert Brian Reese, said when describing why veterans are often surprised by their final rating.
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This approach prevents ratings from exceeding 100% and measures how disabilities compound, not stack.
The Easy Way to Calculate Your Combined VA Rating
If you don’t want to calculate VA Math manually, the simplest option is using a VA disability calculator that already includes:
- VA Math logic
- The bilateral factor
- Current VA pay rates with dependents
That said, knowing how the math works helps you:
- Spot rating errors
- Understand why increases matter
- Plan future claims strategically
How the VA Combined Rating Chart Works?
The VA Combined Ratings Table (38 CFR § 4.25) is the official tool used to calculate your combined disability percentage.
Here’s the core logic:
Step 1: Rank Disabilities from Highest to Lowest
Always start with the highest rating first.
Step 2: Subtract from 100% to Find Remaining Efficiency
A 60% rating means:
- 60% disabled
- 40% efficient
Step 3: Apply the Next Disability to Remaining Efficiency
If the next rating is 30%:
- 30% of 40% = 12%
- New efficiency = 28%
Step 4: Repeat Until All Ratings Are Applied
Once all disabilities are applied:
- Subtract final efficiency from 100%
- Round to the nearest 10%
VA Math Explained with Real Examples
Example 1: Two Disabilities
- 60% disability → 40% efficiency
- 30% of 40% = 12%
- Remaining efficiency = 28%
- Combined disability = 72% → Rounded to 70%
Example 2: Three Disabilities
- 60% → 40% efficiency
- 40% of 40% = 16% → 24% efficiency
- 20% of 24% = 4.8% → 19.2% efficiency
- Combined disability = 80.8% → Rounded to 80%
Example 3: Four Disabilities
- 50% → 50% efficiency
- 30% of 50% = 15% → 35% efficiency
- 20% of 35% = 7% → 28% efficiency
- 10% of 28% = 2.8% → 25.2% efficiency
- Combined disability = 74.8% → Rounded to 70%
“This is why adding a new 10% or 20% condition can sometimes push a veteran into a higher pay bracket,” explained by Brian Reese, said while reviewing combined rating strategies.
Rounding Rules in VA Math (Very Important)
- Final combined ratings are rounded to the nearest 10
- 5 always rounds up
- 94% → 90%
- 95% → 100%
This is why many veterans aggressively pursue additional ratings once they’re near 95%.
What About the VA Bilateral Factor?
If you have disabilities affecting both arms, both legs, or paired joints, the VA applies a bilateral factor:
- Combine the bilateral conditions first
- Add 10% of that subtotal
- Then combine with other disabilities
“The bilateral factor is one of the most overlooked ways veterans lose rating points,” explained by Brian Reese, said when reviewing denied claims.
Why VA Math Matters So Much?
Your combined rating determines:
- Monthly compensation amount
- Eligibility for dependents’ pay (30%+)
- TDIU thresholds
- Access to Special Monthly Compensation
- Whether you’re close to 100% schedular
A small increase can mean hundreds of dollars more per month.
Final Thought
VA Math may feel frustrating, but once you understand it, it becomes a powerful planning tool.
Knowing how the VA Combined Rating Chart works helps you:
- Avoid surprises
- Catch rating mistakes
- Strategically file for increases
- Maximize long-term compensation
“Veterans who understand VA Math make smarter claim decisions and get paid what they truly deserve,” explained by Brian Reese, said in closing.
FAQs
What is VA Math in simple terms?
VA Math calculates how each disability reduces what’s left of your body’s efficiency instead of adding percentages together.
Why doesn’t the VA just add ratings normally?
Because normal addition could exceed 100% and wouldn’t reflect real functional loss.
Can VA Math result in 100% disability?
Yes. A combined rating of 95% rounds up to 100%.
Do mental and physical conditions combine together?
Yes. All service-connected conditions mental or physical use VA Math.
Can VA Math affect TDIU eligibility?
Indirectly. VA Math determines your combined rating, which affects whether you meet schedular TDIU requirements.
