The association say that – currently – 70% of hospital workers are fully vaccinated.
Each hospital will be responsible for setting its own deadline, the organization says.
FOX 5's Evan Lambert says MedStar and University of Maryland Medical System will also require employee vaccinations across their Maryland and Virginia locations.
They say exemptions will be made for medical or religious reasons in compliance with District and federal laws.
"The District of Columbia is blessed with a hospital workforce of over 30,000 individuals that provided and continue to provide compassionate and quality care throughout the pandemic," said Jacqueline D. Bowens, President and CEO of the District of Columbia Hospital Association. "This consensus is a reiteration of our hospitals’ commitment to safety by keeping our staff, patients and visitors protected against COVID-19."
Just over 52% of D.C. residents are partially or fully vaccinated, while just over 42% are fully vaccinated.