How VA Calculates Combined Disability Ratings
Overview
VA disability ratings do not add together arithmetically. Understanding VA's rating calculation methodology helps veterans predict their combined evaluations and make informed decisions about filing additional claims.
Chief's Take: In VA math, 10+10 equals 19, not 20. Do not attempt mental calculations. The system subtracts percentages from what remains of a hypothetical "whole person." Confusing? Absolutely. But once you understand the logic, you can strategize effectively.
The Whole Person Framework
VA begins with the premise that every veteran starts at 100% functional capacity. Each disability removes a percentage from the remaining functional capacity rather than from the original 100%.
Fundamental Principle: Every disability reduces what remains, not the original whole.
Calculation Method
Sequential Process
- Arrange all ratings from highest to lowest percentage
- Begin with 100% representing complete function
- Apply the largest rating first
- Apply each subsequent rating to the remaining percentage
- Round the final calculation to the nearest 10%
Worked Example
Veteran with ratings of 60%, 40%, and 20%:
- Begin at 100%
- Subtract 60%: 100 - 60 = 40% remaining function
- Take 40% of remaining: 40 × 0.40 = 16% additional reduction
- Current total: 60% + 16% = 76% disabled, 24% remaining
- Take 20% of remaining: 24 × 0.20 = 4.8% additional reduction
- Final calculation: 76% + 4.8% = 80.8%
- Rounded result: 80%
Mathematical Formula
For combining two ratings (A and B):
Combined = A + B × (1 - A)
Example with 60% and 40%: = 0.60 + 0.40 × (1 - 0.60) = 0.60 + 0.40 × 0.40 = 0.60 + 0.16 = 76%
Using the Combined Ratings Table
VA publishes official tables for quick reference:
- Locate your highest rating in the left column
- Find your next highest across the top row
- The intersection shows your combined value (unrounded)
- Use that result as your starting point for additional conditions
- Continue until all conditions are combined
- Round the final number
Paired Extremity Adjustments (Bilateral Factor)
When disabilities affect both sides of paired body parts (both legs, both arms, or paired muscles), VA applies an additional 10% enhancement under 38 CFR 4.26.
Application Process
- Combine bilateral ratings using standard VA math
- Add 10% of that combined value (not combine, but add)
- Proceed with combining other conditions
Example
Left knee at 30% + Right knee at 20%: 1. Standard combination: 30% + 20% = 44% 2. Bilateral enhancement: 44% × 0.10 = 4.4% 3. Adjusted bilateral total: 44% + 4.4% = 48.4%, rounded to 48% 4. Combine this 48% with remaining conditions
Bilateral Factor Exclusions
The bilateral factor does not apply to: - Hearing loss - Vision impairments - Certain scar categories - Cranial nerve conditions - Conditions with less than 10% on either side
Rounding Conventions
- Values ending in .5% or higher round up
- Values below .5% round down
- Final combined rating always rounds to nearest 10%
Rounding Examples
| Raw Calculation | Final Rating |
|---|---|
| 74% | 70% |
| 75% | 80% |
| 94% | 90% |
| 95% | 100% |
Special Circumstances
Non-Compensable Combinations
Veterans with multiple 0% ratings may qualify for 10% compensation if the combined non-compensable conditions impair employability. This provision expires if the veteran later receives a compensable rating.
April 2023 Bilateral Factor Update
When bilateral factor calculations cause rounding down from 95% to 94%, VA may exclude the bilateral factor to achieve 100% total rating.
Rating Protection Rules
Certain ratings receive legal protection: - 100% ratings held 20+ years cannot be reduced - Ratings maintained 5+ years require substantial evidence for reduction - Additional protections detailed in Rating Reductions guidance
Quick Reference: Common Combinations
| Two Ratings | Pre-Rounding | Final |
|---|---|---|
| 50% + 50% | 75% | 80% |
| 60% + 40% | 76% | 80% |
| 70% + 30% | 79% | 80% |
| 50% + 40% | 70% | 70% |
| 40% + 40% | 64% | 60% |
| 30% + 30% | 51% | 50% |