"Unincurred business expenses" is the Social Security Administration's (SSA's) name for contributions made by others to a self-employment business effort. These expenses can be deducted from net earnings from self-employment and effect the overall SSI/SSDI amount. Examples include the State Vocational Rehabilitation agency gives their client a computer for their business, or a friend or family member working for a business as unpaid help. If you are self-employed, SSA generally follows the IRS rules to figure your net earnings from self-employment. However, the IRS only allows you to deduct expenses for which you actually paid or incurred debt. When SSA determines whether or not you are engaging in Substantial Gainful Activity (SGA), SSA also deducts unincurred business expenses from your net earnings because SSA wants an accurate measure of the value of your work. NOTE: SSA does not deduct unincurred business expenses from earnings when calculating your Supplemental Security Income (SSI) payment amount. For an item or service to qualify as an unincurred business expense:

• It must be an item or service that the IRS would allow as a legitimate business expense if you had paid for it; and
• Someone other than you must have paid for it.

Source: WorkWORLD: Empowerment Through Decision Support Technology, Employment Support Institute, School of Business Virginia Commonwealth University http://www.workworld.org/wwwebhelp/unincurred_business_expenses_ssi_di_work_incentive.htm

See also Social Security Online