VA Form 21-8940 is where a TDIU claim is documented. It is short, but nearly every part of it is evidence: the disabilities identified, the dates work stopped, the earnings reported, and the education and training listed all feed directly into the decision.
Free accredited representatives help veterans complete this form at no cost. See our guide to finding a VSO. Patriot NEXUS Letters does not prepare or file VA forms.
The disabilities that prevent you from working
The form asks which service-connected disabilities prevent substantially gainful employment. Only service-connected conditions belong here. Listing a condition that is not service connected does not help the claim, and it can muddy the picture the VA is trying to assess.
The strongest answers are specific about function rather than diagnosis: what the condition prevents, how often, and for how long at a time.
Employment history for the last five years
The form asks for the employment held during the five years before the veteran became too disabled to work, including employer names, type of work, hours per week, time lost to illness, and highest gross earnings per month.
These entries are checked against other records. Earnings statements, Social Security earnings records, and personnel files should tell a consistent story. Inconsistencies are one of the most common reasons a TDIU claim stalls.
Dates: when work stopped and when disability began
The form separates the date the veteran last worked full time, the date the veteran became too disabled to work, and the date disability affected full-time employment. They are not always the same date, and the difference can matter for the effective date of any award.
Where veterans start
Every case is different, and there is no obligation at any step. When veterans want to understand what their records actually support, these are the two most common starting points:
- Medical records review
A licensed physician reviews your records for a $250 flat fee and identifies which conditions the available evidence may support. The fee is refunded in full if nothing supportable is identified.
- Nexus letter
When the records support one, a licensed provider writes the medical opinion that addresses the link between your condition and your service or an already service-connected disability.
Education and training
Education, training completed before and after the veteran became too disabled, and any attempts to obtain employment are all requested. This section exists because the VA is assessing whether the veteran's background, combined with the disabilities, still allows competitive work.
How VA Form 21-4192 fits
The VA may send VA Form 21-4192 to former employers, asking what the veteran's duties were, why employment ended, how much time was lost to disability, and whether any concessions were made because of disability.
Employers do not always respond. When they do not, pay stubs, performance records, accommodation requests, leave records, and separation letters can establish the same facts.
Where the form usually goes wrong
The recurring problems are not complicated ones.
- Listing non-service-connected conditions as the reason for unemployability
- Reporting earnings that conflict with tax or Social Security records
- Leaving the employment history blank or incomplete for the five-year period
- Describing the disability in diagnostic terms with nothing about function
- Reporting current work without explaining that it is marginal or performed in a protected environment
The form collects facts; it does not supply medical reasoning. That comes from the record - see our guide to the evidence a TDIU claim rests on and to what substantially gainful employment means.
Frequently asked questions
What is VA Form 21-8940 used for?
It is the Veteran's Application for Increased Compensation Based on Unemployability - the form the VA uses to gather the employment, earnings, education, and disability information needed to decide a TDIU claim.
Is Form 21-4192 required?
It is a request the VA sends to former employers for employment information. A former employer's failure to return it does not defeat a claim, but pay records, personnel files, and separation documents can fill the same gap.
Does filing 21-8940 start a new claim?
TDIU is generally treated as part of a claim for increased compensation rather than a separate benefit. The form supplies the employment evidence the VA needs to decide that question.
Sources
- VA Form 21-8940, Veteran's Application for Increased Compensation Based on Unemployability
- VA Form 21-4192, Request for Employment Information in Connection with Claim for Disability Benefits
- 38 CFR 4.16 - Total disability ratings for compensation based on unemployability (eCFR)
- VA: Eligibility for Individual Unemployability


