The evidence a rater weighs most
VA Nexus Letters: What They Must Say
A nexus letter is the medical opinion connecting your condition to your service — stated to the VA’s “at least as likely as not” standard, reasoned from your records, and signed by a licensed clinician. Below: what yours must contain, condition by condition, and a complete real example you can read before writing a word.
The example: 4,348 words · 11 verified studies · published in full, no account.
What is a nexus letter?
A nexus letter is a written medical opinion from a licensed clinician stating that a veteran’s condition is “at least as likely as not”— a 50 percent or greater probability — connected to their military service, or to a condition the VA has already service-connected. “Nexus” is simply the legal word for that connection. The letter’s job is to give the rater medical reasoning they can weigh: the diagnosis, the theory of connection, and a rationale grounded in the records and the medical literature.
What yours must say — by condition
Each guide covers the diagnostic code, the connection theories that fit the condition, the secondary pathways veterans actually file, and why letters for it get discounted.
- PTSD9411
- Sleep Apnea6847 · 3 secondary pathways
- Tinnitus6260 · 2 secondary pathways
- Hearing Loss6100
- Lumbar Spine5235
- Cervical Spine5235
- Knee Conditions5257
- Shoulder Conditions5200
- Hip Conditions5250
- Migraines8100 · 1 secondary pathway
- Traumatic Brain Injury8045
- Hypertension7101 · 5 secondary pathways
- Ischemic Heart Disease7005 · 3 secondary pathways
- Diabetes Mellitus Type 27913
- Peripheral Neuropathy8520
- GERD7206 · 2 secondary pathways
- Radiculopathy8520
- Asthma6602 · 2 secondary pathways
- Elbow & Forearm Conditions5205
- Ankle Conditions5270
- Flat Feet5276
- Plantar Fasciitis5269
- Carpal Tunnel Syndrome8515
- Cubital Tunnel Syndrome8516
- Deviated Nasal Septum6502
- Sinusitis, Chronic6510 · 1 secondary pathway
- Allergic Rhinitis6522
- COPD & Chronic Bronchitis6600
- Scars7800
- Dermatitis7806
- Psoriasis7816
- Acne7828
- Varicose Veins7120
- Irritable Bowel Syndrome7319 · 1 secondary pathway
- Hemorrhoids7336
- Inguinal Hernia7338
- Erectile Dysfunction7522 · 4 secondary pathways
- Urinary Frequency & Voiding Dysfunction7542
- Meniere's Syndrome6205
- Intervertebral Disc Syndrome5243
- Tibia & Fibula Impairment5262
- Fibromyalgia5025
- Chronic Fatigue Syndrome6354 · 1 secondary pathway
Common questions
What is a nexus letter?
A nexus letter is a written medical opinion from a licensed clinician stating that a veteran's condition is "at least as likely as not" (a 50 percent or greater probability) connected to their military service, or to a condition already service-connected. It bridges the diagnosis and the service connection with medical reasoning a VA rater can weigh.
Who can write a nexus letter?
Any licensed medical professional opining within their specialty — a physician carries the most weight for most conditions. The clinician must review the records, exercise independent judgment, and sign with their credentials. VA Claim Commander drafts the letter from your own records and story; your clinician reviews and signs it.
Does the VA require a nexus letter?
Not formally — but when service connection isn't presumptive or already established, the nexus opinion is usually the deciding evidence. C&P examiners write their own opinion either way; a strong private nexus letter puts a well-reasoned counterweight in the file before they do.
What makes a nexus letter strong?
Four things raters weigh: the exact "at least as likely as not" standard, a named theory of connection (38 C.F.R. § 3.303 direct or § 3.310 secondary), a rationale grounded in the records and the medical literature rather than a bare conclusion, and credentials from a clinician whose specialty covers the condition.