The Oscar-winning actress and star of the new film ‘Lee’ turns 49 on Saturday, October 5

Neil Mockford/WireImage Kate Winslet at the premiere of ‘Lee’ in London on Sept. 3.

Kate Winslet isn’t throwing a party of titanic proportions when she turns 49 on October 5.

Asked by PEOPLE how she plans to celebrate, the Oscar winner says, “Well, it’ll be a quiet one. I like to keep things small.”

She’ll mark her milestone 50th birthday in 2025 without a lot of fanfare either, she told Harper’s Bazaar in August. “I don’t like big parties, and I can’t stand surprises,” Winslet said.

“I want to spend the year doing 50 remarkable things, whether that’s a particular hike I’ve never done, or a place I’ve never been, acts of kindness — I’m gathering a little list,” added Winslet, who shares son Bear, 10, with her husband, Edward Abel Smith, 46, a former exec at Virgin Galactic; son Joe, 20, with ex-husband Sam Mendes; and daughter Mia, 23, with ex Jim Threapleton.

Regardless, Winslet has much to celebrate these days. She produced and stars in the new movie Lee, a film about pioneering model turned World War II photographer Lee Miller. Bringing the story to the screen took nearly a decade, and it’s something she’s particularly proud of considering the obstacles she faced.

Rowben Lantion/BAFTA via Getty Mia Threapleton, Edward Abel Smith and Kate Winslet in 2023.

When Winslet set out to secure financing for Lee, “I came up against men who would say to me, ‘Why should I like this woman?’ I mean, just ridiculous things,” Winslet tells PEOPLE.

Admittedly, she sometimes wondered if the film would ever come together. “‘Oh my God, how is this ever going to happen? How am I going to keep going?’” she says she thought.

But Winslet, with the help of Miller’s son, Antony Penrose and producing partner Kate Solomon, did indeed keep going and made the film, which is now in theaters.

Jesse Grant/Getty Kate Winslet on Sept. 21.

Looking back on her Hollywood career as a whole, which began three decades ago when she starred in Peter Jackson’s 1994 movie Heavenly Creatures, Winslet can’t believe what she’s been able to accomplish.

“The pride I feel is enormous in the things that I have been able to do,” says the seven-time Oscar nominee, who won for 2008’s The Reader.

“And to be able to say that I’m proud of myself matters, because I think that that’s something else I hope to put out there — that women should be able to stand with pride and acknowledge that and not feel like they are bigging themselves up,” she continues.

“It’s a self-acceptance and an awareness of doing something that is challenging and that feels impactful and takes effort like you wouldn’t believe,” she says.

Lee is in theaters now.