The British prime minister said the process of protecting people from coronavirus was already going “exceptionally fast” but “at the moment the limit is on supply” of the vaccine.
“We will be going to 24/7 as soon as we can,” he told MPs.
Health secretary Matt Hancock will set out further details “in due course”, Mr Johnson said.
At prime minister’s questions, Mr Johnson said: “At the moment the limit is on supply, we have a huge network – 233 hospitals, 1,000 GP surgeries, 200 pharmacies and 50 mass vaccination centres and they are going… exceptionally fast.”
Labour leader Keir Starmer said he understood that pilot 24-hour centres were not yet open to the public but there would be a “huge clamour”.
Mr Hancock earlier questioned whether there would be demand for a round-the-clock vaccination operation.
He said the NHS was “absolutely up for doing that” but “most people want to get vaccinated in the daytime, and also most people who are doing the vaccinations want to give them in the daytime, but there may be circumstances in which that would help”.