Often, the effective date for benefits is the date the disability claim was originally filed. In this case, a veteran will typically receive back pay to the date the claim was filed. The VA is liberal in it's interpretation of the 'date the disability claim was originally filed'. A written communication a veteran sent to the VA prior to filing the formal application for benefits can sometimes qualify as the date of filing.
In other cases, the effective date for benefits might be the date the disability first arose. Here, the date a claim was filed or the date evidence was submitted are not key. Rather, what is important is when there was first medical evidence of a disability. Some disabilities may have arisen during service such that the date of discharge will serve as the effective date. Other latent diseases may first occur many years after service and the date of diagnosis may serve as the effective date.
For veterans with Agent Orange related illnesses that are considered presumptive, the rules are more complex. Sometimes retroactive benefits are payable only back to the date that the VA recognized the illness as presumptively related to Agent Orange. This can be the case where a veteran has filed a claim after the VA recognized the illness. In other cases a veteran may be entitled to a much earlier effective date, particularly where the veteran had long ago filed a claim that had been denied before the illness was recognized as presumptively related to Agent Orange exposure.
Determining effective dates for Total Disability based on Individual Unemployability (TDIU) is especially complex. First, an analysis of the date the VA first received evidence indicating the veteran was unemployable will be critical. Next, the veterans degree of disability at the time the VA received the evidence must also be reviewed.
Unfortunately, arguments that a veteran is entitled to an earlier effective date due to VA's failure to notify of the right to file a claim have thus far been unsuccessful.
VA's regulations pertaining to effective dates for retroactive benefits can be quite a labyrinth. It can be helpful to consult a lawyer to advocate through this maze for you. You deserve to have all the benefits you are entitled to.