Visitor numbers will be limited to 10,000 a day to meet social distancing requirements, fewer than half of their pre-Covid levels, operator Sete told AFP.
All floors of the monument will be accessible to visitors, except some areas where renovation work is ongoing.
Only 50 percent of the usual numbers will be allowed in the lifts.
The Eiffel Tower has been undergoing the most extensive revamp of its 130-year history to look its best for the 2024 Paris Olympics, including with a paint job to give it a distinctly golden hue.
But painting was suspended after traces of lead were found in existing layers, making it hazardous to continue.
The re-opening marks the emergence of the 10-tonne metal landmark from its longest closure since World War II.
It was shut down for more than three months during the first Covid wave in the spring of last year, and then again in the autumn.
“After several months of closure, we are impatient to have our staff and visitors back with, of course, a strict compliance with health protocols,” Sete president Jean-François Martins said in a statement.
Online bookings will open on June 1st.
The monument, completed in 1889, usually receives about seven million visitors every year, some three-quarters of them from abroad.
But because of Covid restrictions, it now expects a loss of €70 million for 2021, after a loss of €52 million last year, forcing it to seek fresh financing.
“We cannot absorb both loss-making years with our existing capital,” Martins said, adding he expected the Paris authorities “to help us get through this”.
Disneyland Paris, another tourist magnet, said on Monday it would reopen on June 17th as across France shops, cinemas, tourist sites and café, bar and restaurant terraces reopened on Wednesday.