The fire took hold at the Bampfylde Place retirement home in Great Barr at around 1.30pm yesterday and a woman in her 70s was taken to hospital for further checks.
Firefighters arrived at the scene in less than five minutes thanks to a smoke alarm at the property.
A spokeswoman for West Midlands Fire Service said: "We sent three pumps to the scene. Two from Perry Barr, and one from Erdington.
"Crews acted quickly and assertively in order to rescue a 73-year old lady that is now in ambulance care.
"The smoke alarm actuation meant that we were alerted quickly and were on the scene in less than 5 minutes.
"The cause of the fire is believed to be through careless disposal of cigarettes."
An ambulance spokesperson said: "We were called by the fire service at 1.37pm to reports of a property fire on Thornbridge Avenue, Great Barr, Birmingham.
"The West Midlands CARE team medics, two paramedic officers and an ambulance attended.
"One woman was assessed and treated on scene and was conveyed to Sandwell Hospital for further checks.”
Bampfylde Place is a retirement housing complex which has 79 one bedroom flats.