VA disability claims glossary

Nexus letter

A nexus letter is a medical opinion that explains whether a disability is related to service or to another service connected disability.

Published 2026-04-02

What makes a nexus persuasive

Clear reasoning, record review, and appropriate medical language beat generic templates. The clinician should explain why the conclusion fits your history.

Secondary nexus

For secondary claims, the letter should explain the relationship between the primary disability and the new condition.

Limits

A nexus is evidence, not a guarantee. The VA weighs it with exams and treatment records.

More resources

Try the VA disability calculator, browse VA condition guides, or read in-depth articles.

This information is for educational purposes only and is not legal or medical advice. Rating criteria are summarized from publicly available 38 CFR regulations. Consult a Veterans Service Officer (VSO) or VA-accredited attorney for advice on your specific claim.

Questions about this term

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