Rachel Goodall, a trainee accountant, appeared on the quiz show - a spin-off of The Chase - on Wednesday, January 6.
After securing £2,000 in her cash-builder round, she decided to take on four of the chasers in a timed head-to-head round for the chance to win £25,000.
Rachel was up against professional quizzers Jenny Ryan, Mark Labbett, Shaun Wallace and Paul Sinha in the final round.
The pros had 42 seconds to her 60.
It was an extremely tight finish but Rachel secured the £25,000 cash prize with just one second left on the clock.
Rachel said: "I like doing pub and online quizzes and watching Quiz programmes. The Chase is my favourite. I really liked the last series of Beat The Chasers and the new format so thought why not give it a go.
"I had a figure of £20,000 in my head, as this would make a massive difference to me and my partner Ian, so I aimed to get something around this amount.
"I didn't just want to be greedy. I practiced a lot in the weeks before the show to try my best to revise subjects that I'm not so great on like literature and kings and queens.
"I was so nervous when I was actually up there. It seems like you have more time when you are watching at home and it's over in a flash when you are up there. I tried my best not to look at the clock, so I didn't panic, and tried not to listen to the Chasers questions, so I didn't overload my brain.
"The one time I did look at the clock I had two seconds left and it was my last question.
"When I won I just didn't know what to do with myself, I couldn't believe it. I almost started crying."
She added: "I chose the offer I did based on the amount of time offered, rather than the amount of Chasers. I did think I would take on 3/4 Chasers before I got there, the prospect of taking on them all was very daunting.
"Out of all the Chasers I was the most scared of Mark. His size is just as intimidating as his knowledge.
"When my two chasers to start with included Mark, I thought 'oh no, as I didn't have a choice and would have to face him.
"I wanted to face Jenny the most, as I'm from Yorkshire and she is from Lancashire. I beat Jenny for Yorkshire."
Rachel now plans to spend her money on redecorating her home and putting the rest toward her and Ian's wedding.
She said: "We are looking at getting a new kitchen, and also putting the rest into our wedding fund.
"I still can't quite believe it.
"Ever since, whenever we watch the Chase, when Bradley asks 'Can you beat the Chasers?' I just shout I DID at the tv. The novelty hasn't worn off yet."
Beat The Chasers continues on Thursday night at 9pm on ITV