DEC may stand for:

  • Derwent Entertainment Centre
  • Dheeraj and East Coast LLC
  • Distance Education Council
  • Digital Equipment Corporation
  • Diethylcarbamazine
  • Diethyl carbonate, an ester
  • Disasters Emergency Committee
  • Department of Education and Communities (New South Wales), formerly known as the Department of Education and Training.
  • Department of Environment and Conservation (Western Australia)
  • Department of Environmental Conservation (New York)
  • December
  • Diplôme d'études collégiales, known in English as the Diploma of College Studies