Police were called to Earlham Grove, E7, at 11.56am on Sunday, 26 December, after concerns were raised for the welfare of an occupant.
A body of a woman, believed aged in her 20s, was found at the address. Officers are working to establish her identity and inform next of kin.
A post-mortem examination will be scheduled in due course.
A 26-year-old man was arrested at the scene on suspicion of murder. He has been taken into custody where he remains.
A crime scene has been put in place.
Homicide detectives from the Met’s Specialist Crime Command are investigating.
Enquiries are ongoing to establish the circumstances.
At this stage, the arrested man and the deceased are thought to have been known to each other.
Anyone with information is asked to contact police on 101 or tweet @MetCC and quote CAD2000/26Dec. You can also speak to the independent charity Crimestoppers anonymously on 0800 555 111.