The TDIU back pay formula
Total disability based on individual unemployability, TDIU, pays at the 100 percent rate even when your combined rating is lower. The schedular test in 38 CFR 4.16 asks for one service-connected condition at 60 percent, or two or more with a combined 70 percent and at least one at 40 percent, plus evidence that those conditions keep you from steady, substantially gainful work. Veterans below those thresholds can still be considered on an extraschedular basis, though that route is harder.
TDIU back pay = (100 percent rate minus your current rate) times the months from your effective date to the grant.
Because the 100 percent rate is so far above the 60 and 70 percent rates, the monthly gap is large, $2,503.56 from 60 percent and $2,130.13 from 70 percent. Small differences in the effective date are worth thousands of dollars. For the general version of this math across every rating, use the VA back pay calculator.
Three worked examples with the fee
The fee column assumes a filed agreement at the usual presumed ceiling of 20 percent of past-due benefits. A flat lower percentage is common, so treat it as the high case.
| Case | Monthly gap | Months | Back pay | Fee at 20 percent | You keep |
|---|---|---|---|---|---|
| 60 percent to TDIU | $2,503.56 | 12 | $30,042.72 | $6,008.54 | $24,034.18 |
| 70 percent to TDIU | $2,130.13 | 24 | $51,123.12 | $10,224.62 | $40,898.50 |
| 50 percent to TDIU (extraschedular) | $2,805.68 | 18 | $50,502.24 | $10,100.45 | $40,401.79 |
Look at what happens after the lump sum. In the 70 percent case your check rises from $1,808.45 to $3,938.58 every month, and the attorney is never paid again. The fee is a one-time slice of money you did not have yet. If the claim is denied, there is no fee, because nothing is owed before a favorable decision.
What sets the months owed
The months column drives everything, and three rules matter most for TDIU.
- TDIU rides with the increase claim. Under the Court of Appeals for Veterans Claims decision in Rice v. Shinseki, a request for unemployability can be part of a claim for a higher rating. If you filed an increase and your evidence shows you could not work, the TDIU effective date can follow that filing date.
- The one-year lookback. For increases, 38 CFR 3.400(o)(2) allows an effective date up to a year before the claim when the record shows the condition worsened in that window. Employer letters and treatment notes from that year are what prove it.
- Continuous pursuit. After a denial, filing a supplemental claim, higher-level review or Board appeal within one year keeps the original effective date alive. Missing that window can cost you a year or more of the months in the table.
This is also where veterans lose money by filing a thin form and waiting. A claim that includes VA Form 21-8940, work history, a treating doctor's statement on functional limits and a clear end date for work gives the rater less reason to dispute the date. See the TDIU lawyer page for how attorneys build that file.
When an attorney pays for itself
A fee of $6,000 to $10,000 sounds large next to a $0 fee at a veteran service organization, and for a clean first TDIU claim free help may be enough. The case for paying changes after a denial. Rice-type effective date arguments, vocational evidence and the choice between the three review lanes are where a few months, or the whole grant, are decided. One extra month at the 70 percent gap is $2,130.13, so a representative who protects six months of the date covers most of a 20 percent fee on their own.
What to check before you sign: the fee agreement must be in writing and filed with VA, no fee can be charged before the initial decision, and the representative must be accredited. Our guide to the VA disability attorney fee agreement lists the clauses to read, and what a VA disability lawyer costs covers the extras. Verify accreditation in the VA Office of General Counsel search.
If you also applied for Social Security disability, the two claims run separately and have different fee rules. Read SSDI lawyers for veterans before hiring anyone to handle both. TDIU back pay is not taxable income, per IRS Publication 525.
TDIU back pay FAQ
How much back pay do you get with TDIU?
It is the monthly gap between your current rate and the 100 percent rate, times the months from your effective date to the decision. A veteran at 70 percent who waited 24 months is owed $51,123.12 before any fee, using the rates effective December 1, 2025.
How is TDIU back pay calculated?
VA pays the 100 percent rate from the effective date, so take that rate minus what you were paid, then multiply by the months owed. The effective date is usually the day VA received your TDIU or increase claim, or up to a year earlier if the evidence shows you could not work then.
How long does it take to get TDIU back pay after approval?
VA normally pays retroactive pay as one lump sum within a few weeks of the decision letter. If nothing arrives after about 30 days, check claim status on VA.gov or call VA. Some of it may be held if VA proposes a fee payment to your representative.
Is TDIU back pay taxable?
No. Federal law excludes VA disability compensation from gross income, and that covers retroactive pay. You do not report it on your federal return. The IRS lists veterans' benefits as excluded in Publication 525.
Does a lawyer take a percentage of TDIU back pay?
Yes, if you hire one. An accredited attorney may charge nothing before VA's first decision, then up to 20 percent of past-due benefits under a filed written agreement. On a $51,123.12 award that is $10,224.62, paid from the back pay and not from your monthly check.