But the World Health Organisation (WHO) warned there could still be flare-ups of the disease in the region, which has suffered the world's deadliest outbreak over the past two years, as survivors can carry the virus for many months and could pass it on.
Liberia was the last affected country to get the all-clear, with no cases of Ebola for 42 days, twice the length of the virus's "incubation period" — the time elapsed between transmission of the disease and the appearance of symptoms.
The other affected countries, Guinea and Sierra Leone, were declared Ebola-free late last year. There were cases in seven other countries including Nigeria, the United States and Spain, but almost all the deaths were in the West African nations.
The WHO announcement on Thursday is a major step in the fight against a disease that began in the forests of eastern Guinea in December 2013 before spreading to Liberia and Sierra Leone. It overwhelmed medical infrastructure in the region which was ill-equipped to deal with the outbreak, and at its height in late 2014 sparked global fears among the general public.
With those memories still fresh, and society and the economy still reeling from the outbreak, the reaction to Thursday's announcement was muted. There was no signs of celebration such as the "Ebola free" T-shirts that people wore after previous WHO announcements.
Experts said progress had been made in the region's response to Ebola, with new cases having dwindled due to public health campaigns, efforts to trace and isolate potential sufferers and the safe treatment and burial of patients and victims.
Hundreds of healthcare workers in both urban and rural communities were among those killed by the disease, a major blow to medical systems in countries which already had among the lowest numbers of doctors per head of population in the world.
"The world is still worryingly underprepared for potential future health threats and a change of mind-set is required to ensure we invest in research and development today to protect ourselves in years to come."
Hilde de Clerck, a doctor with Doctors Without Borders who has assisted with five Ebola outbreaks including in Congo, Uganda and the latest epidemic in West Africa, said vigilance was crucial to prevent the re-emergence of the disease, for which there is no proven drug treatment, although researchers have developed a vaccine.
While WHO and other health specialists say another outbreak of this magnitude is unlikely, and much has been learned in terms of monitoring patients and responding to outbreaks, problems remain, including with simple hygiene, such as not washing hands.
Mohammed Kamara, who lives in Monrovia, lost two relatives and a friend to Ebola in 2014. "I know exactly what it means to have the disease in the country," he said.