The HCA Day Hospice is closed until Feb 1 after a fire broke out at the HCA Hospice Care headquarters in Serangoon Road on Tuesday.
Patients of the hospice will be cared for at home and meals will be delivered to those in need.
Patients and their families have been informed, said HCA Hospice Care in a statement on Wednesday.
It added that the affected office, which is in Block A of Kwong Wai Shiu Hospital (KWSH), is expected to be closed for at least two months for cleaning and recovery.
All operations staff will work from home, while affected clinical staff will be relocated to another office at the HCA headquarters.
"While we are managing the damage and working towards full recovery of operations caused by this unfortunate incident, our commitment to serve terminally ill patients in their homes remains strong," said chief executive of HCA Hospice Care Angeline Wee.
The affected office is on the third floor of Block A.
The Singapore Civil Defence Force said it was alerted to the fire at about 8.25pm on Tuesday and that the fire was extinguished using a water jet.
There were neither any injuries reported nor an evacuation ordered.
SCDF is still investigating the cause of the fire.
In a Facebook post on Tuesday night, KWSH said no one was in the office at the time.
The hospital's nursing home residents are housed in a separate block. Its wards have been checked and no residents were affected by the fire, added KWSH.
Its other operations in Block A, which houses Fresenius Kidney Care, Healthway Medical, Silver Generation Office @ Kallang and the KWSH canteen, resumed their operations on Wednesday.