Volunteers are extremely valuable to the charitable sector: Urban Institute researchers estimated the value of their labor at $163 billion in 2013. Though charitable contributions can be deducted from income taxes, volunteers cannot deduct the value of their labor. By economic consensus, donations of time and money are complements, meaning when people increase monetary donations they also tend to volunteer more hours. This Tax Policy and Charities brief explores how potential ways to create a tax deduction for volunteer labor would affect charitable donations, as well as the supply of volunteer labor.