Civic obedience and more time to prepare, according to one expert.
More preparation time and people obeying confinement measures has helped Portugal manage its coronavirus outbreak, it's been claimed.
Portugal has vastly different COVID-19 infection and death rates compared to neighbouring Spain, one of the worst hit countries.
Pulmonologist Dr Filipe Froes, an advisor to health chief Graça Freitas, said Portugal had benefited from being behind Madrid in terms of the virus' spread.
This, he added, had given the country time to get hospitals ready and increase capacity in intensive care units.
"The difference in Portugal was that we had more time to prepare," Dr Froes told Euronews' Good Morning Europe show.
"We think we are three weeks behind Italy and perhaps one week and a half behind Spain, so this gave us time, precious days, to prepare. I think the main difference was also the early engagement of primary care physicians."
Portugal declared a state of emergency on 18 March, just two days after the first COVID-19 death was reported.
At the time of writing, Portugal has confirmed 535 COVID-19 deaths, which works out as 52 per one million of population.
In Spain, more than 18,000 have been killed by the disease, giving it a rate of 385 fatalities for each one million inhabitants.
Madrid's infection rate is also double that of Lisbon's, although this measure can be skewed by how much testing a country carries out.
Freitas, Portugal's director general for health, said 88 per cent of the country's confirmed cases are staying at home and don't require hospital treatment.
"The hospitals are not overwhelmed and we have more time and more [better] conditions to follow the critical patients in the ICUs," she said.
"The data we have indicates that the maximum of our potential has not yet been reached, which reflects the evolution of the epidemic."
'Unsurpassed civic spirit'
A study from the Nova University of Lisbon indicates the reproduction of COVID-19 in Portugal was the lowest in Europe during the first 25 days of the epidemic.
Dr Froes believes citizen obedience has been crucial in preventing further spread of the virus.
"Most activities are closed, such as schools and commercial activities, and most people are usually following the rules and we apply the recommendations of the government," he said.
Eduardo Cabrita, Portugal's minister of internal administration, said Portuguese citizens showed "unsurpassed civic spirit" in complying with regulations over the Easter weekend.
"Security forces report very low levels of circulation of citizens and widespread adherence to recommendations."
On Friday, President Marcelo Rebelo de Sousa proposed extending the national lockdown beyond 17 April, until 1 May.
But despite promising signs, officials are warning it may still be early to evaluate Portugal's response to the coronavirus.
"The area of housing in residential homes and their workers is identified as of particular concern and priority for action," said Cabrita.
Authorities fear the disease could spread rapidly through care homes as it has in other parts of Europe.
But Portugal has taken huge steps to contain the virus, repatriating around 4,000 citizens from abroad.
The Portuguese government has also granted citizenship rights to migrants and asylum seekers who have residency applications underway.
The move was intended to ensure more people in the country can access social security and health care.