It does not cost anything to hire a Social Security Disability lawyer. The process is much the same as when you hire a personal injury attorney. In an SSD case, when you are approved for disability benefits, your attorney receives a percentage of your back-pay award—usually 25 percent up to a maximum of $6,000. Because it usually takes long for an SSD appeal to be successful, there is usually back-pay in the form of a lump sum payment.