The Combined Ratings Table
The VA does not add your disability ratings together. Under
38 C.F.R. § 4.25
the VA uses a "combined ratings table" that applies each rating to your remaining "healthy" percentage. Per M21-1, Part IV.ii.2.A, the RVSR applies ratings in descending order from highest to lowest.How It Works: Step by Step
EXAMPLE: 50% + 30% + 20%
Step 1: Start at 100% healthyStep 2: Apply highest rating first: 50% of 100 = 50
→ You are now 50% disabled, 50% healthy
Step 3: Apply next rating to remaining healthy: 30% of 50 = 15
→ Combined: 50 + 15 = 65% disabled, 35% healthy
Step 4: Apply next rating to remaining: 20% of 35 = 7
→ Combined: 65 + 7 = 72% disabled
Step 5: Round to nearest 10: 70%
Simple addition: 50 + 30 + 20 = 100%
VA math: 70%
Monthly difference: $3,938.58 vs $1,808.45 = $2,130.13/mo gap
The Bilateral Factor
Under
38 C.F.R. § 4.26
when you have disabilities affecting both sides of the body (both knees, both arms, left knee and right hip, etc.), the VA adds a "bilateral factor" of 10% of the combined bilateral rating before combining with non-extremity conditions. This can push you over a rounding threshold.BILATERAL FACTOR EXAMPLE
Right knee: 20% | Left knee: 10%Combined bilateral: 28%
Bilateral factor: 10% of 28 = 2.8
Bilateral total: 28 + 2.8 = 30.8 (rounds to 31)
Without bilateral factor: 28% → rounds to 30%
With bilateral factor: 30.8% → rounds to 30% (same here, but in other scenarios it pushes over)
The Rounding Rules
The VA rounds to the nearest 10%. Per
38 C.F.R. § 4.25
combined values ending in 5 or higher round up, below 5 round down. This means 74.5% rounds to 70%, but 75% rounds to 80%. This is why every percentage point matters and why secondary conditions at even 10% can push you over a rounding threshold worth hundreds of dollars per month.Why This Matters for Strategy
Understanding VA math reveals two critical strategy points. First, each additional rating has diminishing returns because it's applied to a smaller remaining healthy percentage. Second, the most impactful ratings are the first ones - getting from 0% to 50% is a bigger jump than 50% to 70%. But small secondary claims (10-20%) can push you past critical rounding thresholds (e.g., from 74% to 76%, which rounds to 80%).