The airport was closed at the weekend as the eruption, which has forced the evacuation of thousands and destroyed hundreds of homes, intensified.
Smoke from the volcano extends more than two miles into the air over the islands, the BBC reports, which airport authorities said made flights impossible.
Although the airport reopened late on Sunday (26 September), many flights were showing as cancelled on Monday (27 September) – both arrivals and departures.
"At this moment, all Canarian airports are operational again," said the airport. "There are airlines that are suspending their flights to/from La Palma.