Workers walked out in protest at a new access policy that has seen separate lifts allocated to visitors with pre-booked tickets and those who buy them on site.
At the same time, the tower now sets aside half of daily tickets for internet customers, up from just 20 percent previously.
Workers said the changes resulted in lopsided queues that could extend to three hours for those waiting to pay for tickets, and up to an hour for internet customers who are supposed to have reserved time slots.
But late Thursday, management and unions said that the tower would reopen on Friday.
Earlier workers had demanded more flexibility in managing the thousands hoping to reach the top of the “Iron Lady” each day during the peak summer tourist season.
The tower's operator said, however, that queues were no worse than before, even as visitor numbers have risen, with more than 6.2 million tickets sold last year.
Many tourists arriving on Thursday morning had no idea what the strike was about, with signs saying only that the monument was closed.
“I'm annoyed, I'm not going to lie,” said Robin Frye of Birmingham, England, who was visiting Paris for the first time.
“It's going to throw off our whole trip if I'm honest,” she said.
“We got up at 6:00 am and were among the first people here, but it's closed,” said Adele Liliane, who arrived this week from Montreal, Canada.
Earlier Thursday workers held a general assembly to discuss a proposal offered by the site's operator SETE, which is majority owned by the city of Paris.
“The SETE is well aware of the disappointment for visitors because of the monument's closure, and its negative impact on the image of both the city and country,” the company said in a statement.
“It offers its apologies to everyone — Parisians and French as well as foreign tourists.”
The tower's 300-strong staff has staged strikes repeatedly in recent years over issues including pickpocketing and maintenance work.
“It's unfortunate to end up here, with visitors being penalised, but we did everything to avoid it,” said Denis Vavassori of the CGT union.
He said directing people to the elevator with the shortest waits regardless of the type of ticket they bought, as they used to do, would ease the congestion.