The plain-language read
What is a nexus letter?
A nexus letter is the independent medical opinion the VA asks for when your service treatment records don’t directly prove that a current diagnosis is connected to your military service. This page walks through what one is, what it has to contain, why it carries weight at the VA, and what to look for before you pay a single clinician for one.
Need the condition-by-condition picture first? Open the PTSD nexus-letter guide — or jump to the VetVerity directory to see who actually writes these letters in your state.
Five practical questions
Start with the answer you need right now.
These short companion guides turn the big picture into a next step — before you book a clinician, send records, or spend money on a letter.
Does the VA accept nexus letters?
What the VA weighs, and why a letter never guarantees an outcome.
Read this answerHow long does a nexus letter take?
The typical 2–6 week range and what starts the clock.
Read this answerWhat does a fair nexus letter cost?
The usual $600–$900 range, plus the separate $25 directory unlock.
Read this answerHow do I vet a clinician?
Credentials, records review, pricing, timelines, and red flags to check.
Read this answerWhat evidence helps a clinician write a strong letter?
The diagnosis, service records, event details, timeline, and statements to gather.
Read this answer
Section 1
A medical opinion that links your diagnosis to your service.
The word “nexus” means a link. In a VA disability claim, the nexus is the connection between an in-service event, injury, or exposure and a current medical diagnosis. The VA has to see that link to grant service connection — and most claim denials turn on it, not on whether the diagnosis itself is real.
A nexus letteris a written, signed medical opinion that fills in that link. It is written by a licensed clinician — usually a private provider outside the VA — and it addresses three things inside one document: the current diagnosis, the in-service event, and the clinician’s clinical opinion that one is at least as likely as not related to the other.
The letter is not a treatment record. It is not a buddy statement. It is not a VA C&P exam report. It is its own deliverable, paid for separately, and it lives or dies on the strength of its clinical reasoning.
Where it fits in the claims process.
Section 2
What a strong nexus letter must contain.
A handwritten paragraph on a prescription pad isn’t enough. The VA reads the letter as a piece of medical reasoning, and four parts have to be present for it to do its job. If any of them is missing, the rater can — and routinely does — discount the opinion.
- 01
A clear current diagnosis.
A current clinical diagnosis, named by DSM-5 or ICD-10 code where applicable, with the date it was established. The VA needs to see what condition is actually being claimed and on what evidence that diagnosis rests.
- 02
A specific in-service event, injury, or exposure.
The letter has to name the in-service event — a documented incident, a treatment note, an exposure window, a date range — not a vague reference to “service treatment records.” Specifics are what let the rater tie the opinion to your claim.
- 03
A clinical opinion linking the two.
The opinion itself, expressed in the VA’s own probabilistic language — “at least as likely as not” (≥50% probability). Words like “possible” or “cannot rule out” read as speculation and routinely weigh less than what the law asks for.
- 04
Clinical rationale, credentials, and a real signature.
The reasoning that connects event → diagnosis → current symptom → impairment, the clinician’s credentials and license (MD, DO, PhD, PsyD, NP, PA), and a wet-or-electronic signature on letterhead with a date. A letter unsigned, or unsigned on letterhead, is treated as a draft.
Section 3
Why the VA reads it the way it does.
The VA is evidence-bound. A claims processor (the “rater” who decides your case) cannot grant service connection on inference or good faith alone — only on the record in front of them. The nexus letter is one of three pieces that almost every successful claim relies on, alongside the current diagnosis and the in-service event:
- A current diagnosis — usually from a current clinical note.
- An in-service event — service treatment records, a buddy statement, a deployment / exposure record.
- A medical nexus — the opinion linking the two above, on letterhead, from a licensed clinician.
The phrase “at least as likely as not” isn’t a slogan. It is a legal standard — the level a rater needs to meet to grant service connection. A letter that says “it is possible” or “I cannot rule out” can be weighed as opinion rather than evidence; a letter that says “it is at least as likely as not, and here is the reasoning” reads as evidence.
That is also why the letter should arrive beforethe C&P exam. A strong nexus letter in the file frames the exam; an absent one leaves the rater to assemble one from a short VA-contracted encounter that the veteran may have under-described.
Section 4 · Vetting
What we verify before a profile goes live.
VetVerity is not a paid listing and the $25 unlock doesn’t buy a letter. It buys a vetted, vetted directory — a discovery layer with documented evidence on file per profile, so you don’t have to take a stranger’s word that they write these letters. Three checks per profile, before a clinician is listed:
- 01
A recent letter on letterhead, in the right category.
We confirm a recent letter on letterhead for a similar claim category — PTSD, MST, sleep apnea, tinnitus, hearing loss, musculoskeletal, toxic exposure, or whatever the relevant category is. Profiles declare the categories they will and will not write for.
- 02
A license that matters, on file with the NPI.
MD / DO / PhD / PsyD / NP / PA. Specialty, board certification, and an active NPI number are verified before a profile goes live — and re-checked on a schedule, not just at signup.
- 03
Reachable inside the veteran’s timeline — at a published price.
Telehealth availability in the veteran’s state, current in-person service area, and a published pricing tier ($, $$, or $$$, with the dollar range on the profile) — so the veteran can call the right offices without guesswork, in the right window.
What the $25 is, and isn’t
The $25 unlocks the discovery layer — not a letter.
VetVerity is the discovery layer in front of the clinician. The $25 lifetime fee unlocks the contact details, the credentials, the service area, the pricing tier, and the writing-confirmation of every profile in the directory. The letter itself is paid directly to the chosen clinician at their published tier — these are two separate transactions, on purpose. VetVerity does not take a cut of the letter fee, does not resell letters, and does not mark up the per-letter cost.
Want the full read on how the directory is built? The About page spells out the difference between a Nexus Letter Specialist and a Veteran-Friendly Practice — the two kinds of profiles the directory surfaces.
Now you know what it is — here is who writes one
Browse vetted specialists who write nexus letters for your specific condition.
Every profile in the VetVerity directory is tagged by condition and service type. Filter to your state, pick the right clinician, and come back to the claims walkthrough ready to file with a strong file.
Get a nudge when coverage expands.
One short alert when a new nexus-letter specialist joins the directory in your state, or when coverage grows. Your email stays with VetVerity; no third-party list, no spam.