Nexus Letter for Migraines
Migraine claims turn on documented frequency and on the word "prostrating."
Migraines are frequently claimed secondary to a service-connected head injury, neck condition, or mental-health condition, and frequently underrated because the evidence never captures how often the attacks actually stop the veteran from functioning. VA evaluates migraines largely on the frequency of prostrating attacks — episodes that force you to stop what you are doing and lie down. A nexus letter that establishes the link but says nothing about frequency wins service connection and loses the rating.
Check this first: is migraines presumptive for you?
If a presumption applies to your service, VA connects the condition without requiring you to prove the medical link — which can mean you do not need a nexus letter at all. Presumptions turn on where and when you served, so read the qualifying service line before assuming one fits.
- Gulf War Illness — undiagnosed / chronic multi-symptom
Applies to: Active military service in the Southwest Asia theater on or after 8/2/1990 (no end date).
38 CFR § 3.317
VA's published list →
Limits that change the answer
- !Gulf War Illness — undiagnosed / chronic multi-symptom: CRITICAL DEADLINE: Condition must manifest to a compensable (10%+) degree by 12/31/2026 under the current 38 CFR § 3.317 rule. If manifestation is post-2026 and the rule is not extended, this presumption will not apply — flag this for any vet whose manifestation date is unclear or approaching the deadline.
- !Gulf War Illness — undiagnosed / chronic multi-symptom: Distinct from PACT Act burn-pit presumptions — a single vet may qualify under both.
Presumptive lists last reviewed 2026-04-19. Rendered from our tracked copy of VA's published lists, not retyped per page.
What every nexus letter must do
These four apply to every condition. A letter missing any one of them is the most common reason an otherwise good claim is denied.
- 1.A statement that your records were reviewed
VA weighs a medical opinion partly on whether the clinician actually had the evidence in front of them. A letter that does not say what was reviewed reads as an opinion formed without the file.
- 2.A current diagnosis
Service connection requires a present disability. The letter should state the diagnosis plainly rather than describing symptoms and leaving the conclusion implied.
- 3.The phrase "at least as likely as not"
This is VA's evidentiary standard — a 50 percent or greater probability. Under 38 CFR § 3.102 the tie goes to the veteran, and this phrase is what places the opinion at or above that line. Softer wording ("possibly," "may be," "could be," "cannot rule out") sits below the standard and is a leading cause of denial.
- 4.A stated medical rationale
The reasoning behind the conclusion, not just the conclusion. An opinion that gives an answer without explaining the basis for it carries little weight, no matter how well-credentialed the signer.
What migraines letters must establish on top of that
- ›The link to service or to the service-connected condition — most often a traumatic brain injury, a cervical spine condition, or a mental-health condition.
- ›How often prostrating attacks occur, in the clinician's own assessment. This is the term VA's rating criteria are built around and its absence is felt.
- ›The functional effect during an attack: what you cannot do, and for how long.
Most common secondary pathways for migraines
Under 38 CFR § 3.310, a condition caused or permanently worsened by an already-service-connected condition is itself service-connected. These are the primaries migraines is most often claimed behind:
- ›Traumatic brain injury (TBI)
- ›Cervical spine (neck) conditions
- ›PTSD, depression, or anxiety
- ›Sinusitis or rhinitis
The primary has to already be service-connected. If it is not, that claim comes first.
What gets migraines letters discounted
- !A headache diary is one of the few pieces of evidence a veteran can build without a doctor, and it directly supports the frequency finding the rating depends on.
- !If migraines are being claimed secondary to TBI, the letter should be explicit about that, since headaches can otherwise be folded into the TBI evaluation rather than rated on their own.
- !"Occasional headaches" in a treatment note will be read against you if the letter claims frequent prostrating attacks. The letter is stronger when it reconciles the two.
Draft the migraines letter — free
Our drafter builds the VA-compliant framing and language for your doctor to review, edit, and sign. It is free, there is no account and no card, and the medical judgment stays with your physician — we write the structure, not the opinion.
Draft my migraines nexus letter →Opens the drafter with migraines and the secondary theory already filled in. You can change both.
Also useful for migraines claims
- Migraines rating criteria — what each percentage requires, and what it pays.
- Real Board grants for migraines — verbatim language from decisions that were actually granted.
- What nexus letters cost — what you are paying for, and when you do not need to pay at all.
- C&P exam prep — the questions the examiner will ask and how to answer them.
Nexus letters for other conditions
NexusVetClaims provides software, not legal representation or medical advice. We are not VA-accredited and never take a percentage of your benefits. A nexus letter is a medical opinion — only a qualified clinician who has evaluated you can provide one. Regulations cited here are current as published on eCFR; verify anything load-bearing against the source before you file.