To be eligible for either TDIU or SSDI, a veteran must generally (there are some slight exceptions) be unable to work due to physical and/or mental disabilities, but there are also some important differences. For example, the VA only considers a veteran’s service-connected disabilities while SSA considers all disabilities. Additionally, a veteran may be eligible for TDIU if their disabilities keep them from doing their past work, while for SSDI, being capable of doing any job may be a disqualifier. Finally, the VA cannot consider a veteran’s age for TDIU, while age is one of the most important factors in an SSDI claim.