Why 50 + 50 Doesn't Equal 100%: The VA's Combined Ratings Formula

It's one of the most confusing aspects of the VA system: two 50% disabilities don't equal 100% combined. Neither do three 40% ratings. The math feels wrong — until you understand how the VA actually calculates it.

The "Whole Person" Method

The VA starts with the idea of a "whole person" — 100% ability. When you have a disability, it takes away some of that ability. A 50% rating means you've lost 50% of your whole person.

Now for a second disability: you don't apply it to 100%, you apply it to the remaining 50%. A 30% rating on the remaining 50% removes 30% of 50%, which is 15. So your total is 50 + 15 = 65%.

Working Through an Example

Say you have a 70% rating, a 50% rating, and a 30% rating:

1. Start: 100% whole person
2. Apply 70%: removes 70 from 100. Remaining: 30. Running total: 70.
3. Apply 50%: removes 50% of 30 = 15. Remaining: 15. Running total: 85.
4. Apply 30%: removes 30% of 15 = 4.5. Remaining: 10.5. Running total: 89.5.

89.5% rounds to 90% (values at 5 or above round up to the next 10).

How Rounding Works

The VA first rounds to the nearest whole number, then rounds to the nearest 10. A combined value of 45.1% rounds to 45%, then to 50%. A 44.9% rounds to 45%, then also to 50%.

This means if you're at 45% combined, you're getting paid at 50%. At 85%, you're at 90%. At 95% or above, you reach 100%.

Try It Yourself

Our Combined Rating Calculator walks you through the math for your specific ratings, step by step, with a full breakdown table.