Straight answers on VA claims & nexus letters.
Plain-English guides written for veterans and reviewed by board-certified physicians — so you can file with clarity, not guesswork.
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Jump to the section that matches where you are: evidence, common conditions, secondary claims, presumptives, ratings, or appeals.
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The plain-English guides that help veterans understand what the VA needs before filing or adding evidence.
VA disability conditions: a plain-English guide to what’s claimable
A map of the most-claimed VA disability conditions, grouped by body system, with a detailed guide for each. Start here to find yours.
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The evidence checklist every VA claim needs
A VA claim is only as strong as its evidence. A clear checklist of what to gather before you file, so nothing gets missed.
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C&P exam vs. nexus letter: what the difference means
They are not the same, and confusing them costs claims. What each is, how the VA weighs them, and what to do after a negative C&P exam.
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How to submit a nexus letter to the VA (step by step)
A strong nexus letter only helps if it reaches the right place at the right time. How to submit it to the VA correctly.
Read guideSleep, hearing & respiratory
Guides for high-volume claims where the service connection is often the hardest part to prove.
Sleep apnea VA claims: connecting it to your service
One of the most commonly denied claims, usually over the service connection. How the VA rates sleep apnea and what evidence makes the link.
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Sleep apnea secondary to PTSD: the most common secondary claim
If you already have a PTSD rating, sleep apnea may be claimable as a secondary condition. How the connection works and what the VA needs to see.
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Hearing loss nexus letters: proving noise exposure
Hearing loss is rated by a strict test formula, not by how much you struggle. How the VA measures it and what a nexus letter must prove.
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Nexus letters for tinnitus: what the VA looks for
Tinnitus is the number-one claimed VA disability, rated at a flat 10 percent. Here is what the VA looks for and how a nexus letter can support your claim.
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Burn pit exposure claims: what qualifies under the PACT Act
If you served near burn pits, many respiratory conditions and cancers are now presumptive. What qualifies and how the claim works.
Read guideMental health & PTSD
PTSD, MST, depression, anxiety, and the secondary claims that often grow out of chronic pain or other disabilities.
PTSD nexus letters: what makes a medical opinion credible
For PTSD claims, the credibility of the medical opinion often decides the outcome. What makes a PTSD nexus letter carry weight with the VA.
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Depression and anxiety secondary to a service-connected condition
Living with chronic pain or a serious service-connected condition takes a mental toll. How to claim depression and anxiety as secondary conditions.
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Chronic pain and depression: how one claim leads to another
Chronic pain does not stay physical; it wears on mental health. How depression secondary to chronic pain works as a VA claim.
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Military sexual trauma (MST) claims: evidence and markers
MST-related claims follow special, relaxed evidence rules. What “markers” are, how the VA evaluates MST claims, and what support is available.
Read guideBack, joint & nerve pain
The back, neck, knee, nerve, and migraine claims veterans often need to connect to service or another rated condition.
Nexus letters for back pain and lumbosacral strain
Back injuries are among the most common VA claims. How the VA rates lumbosacral strain, why range of motion matters, and how to connect it to service.
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Nexus letters for knee conditions: limitation of flexion explained
Knee problems are one of the most common VA claims. How the VA rates limitation of flexion and instability, and what a nexus letter needs to show.
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Sciatica and VA claims: connecting nerve pain to service
Sciatica, radiating nerve pain down the leg, is frequently claimed as secondary to a service-connected back condition. How the VA rates it.
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Neck pain (cervical strain) nexus letters: what you need
Neck pain from cervical strain is a common, overlooked VA claim. How the VA rates it and what a nexus letter needs to establish.
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Radiculopathy secondary to back conditions: what to know
Nerve pain radiating into your arms or legs from a service-connected back is often a separate, ratable secondary claim. How radiculopathy works.
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Migraines and VA disability: how the VA rates prostrating attacks
Migraines are more than bad headaches; the VA rates them on prostrating attacks. How the rating works and why documentation is everything.
Read guideRatings, secondary claims & back pay
How VA math, secondary conditions, protection rules, TDIU, permanent status, and effective dates affect monthly compensation.
Understanding VA disability ratings and combined rating math
VA math is not simple addition. How combined ratings actually work, why 30 plus 20 is not 50, and what each level pays in 2026.
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Secondary conditions: how to increase your VA rating
One service-connected condition often causes others. Claiming those secondary conditions is one of the most overlooked ways to raise your combined rating.
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The VA 5, 10, and 20-year rules: protecting your rating
The VA can sometimes reduce a rating, but three time-based rules protect veterans. How the 5, 10, and 20-year rules work.
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Permanent and Total (P&T) disability: what it means
Permanent and Total status is more than a 100% rating. It means no routine re-exams and can open added benefits for your family.
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TDIU: getting the 100% rate without a 100% rating
If service-connected conditions keep you from working, TDIU can pay at the 100% rate even without a 100% rating. How it works.
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VA effective dates and back pay: how far back your money goes
Your effective date decides how much back pay you get — sometimes years of it. How effective dates work and how to protect your earliest one.
Read guidePresumptive & toxic exposure claims
Where the VA may presume service connection because of where you served, what you were exposed to, or when you served.
The PACT Act explained: what it means for your VA claim
The PACT Act added dozens of presumptive conditions for toxic exposure. What it covers, who qualifies, and what it means if you were denied before.
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Agent Orange presumptive conditions: the 2026 list and locations
Agent Orange presumptions now cover more conditions and more locations than most veterans realize. The updated 2026 picture.
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Gulf War Illness claims: undiagnosed symptoms and service connection
Gulf War Illness covers symptoms medicine cannot fully explain. How the VA evaluates these claims and who qualifies.
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Camp Lejeune water contamination: VA disability claims
If you served at Camp Lejeune between 1953 and 1987, eight conditions are presumptive. What qualifies and how to file.
Read guideDenials, doctors & strategy
What to do after a denial, how to challenge weak exams, and how to choose the right medical opinion for your claim.
How to win a VA claim after a denial
A denial is not the end. Your appeal options, including the supplemental claim, and how new evidence like a nexus letter can turn it around.
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Rebuttal letters: how to counter a bad C&P exam
A bad C&P exam can sink a claim, but it does not have to. How a rebuttal letter challenges a flawed opinion and what makes it work.
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Bad discharge, still benefits? The character of discharge review
An other-than-honorable discharge does not always block VA benefits. How a character of discharge review works, and who may still qualify after the 2024 rule change.
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How to find a nexus letter doctor you can trust
Not every doctor can write a strong nexus letter. Who qualifies, what separates a strong provider from a weak one, and how to choose.
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Nexus letter vs. DBQ vs. IMO: what’s the difference?
Nexus letter, DBQ, IMO — they sound alike and get confused. What each is and when it helps your claim.
Read guideFind the guide for your claim.
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Connecting veterans with board-certified physicians who write clear, credible nexus letters for VA disability claims.
Veterans Benefits Unlock is a private service and is not affiliated with the U.S. Department of Veterans Affairs or any government agency. A nexus letter is a medical opinion and does not guarantee any specific VA rating or claim outcome. Always consult an accredited representative regarding your claim.