Minchin first appeared on the programme in 2001, and went on to replace Sian Williams as a full-time member of the team when the show moved from London to Salford in 2012.
This is everything you need to know.
What did she say?
Minchin confirmed the news earlier this year, on 8 June.
At the time, she said: “It will be this year, 20 years since I first presented this programme. Since then, I’ve felt part of a huge, enormous BBC Breakfast family, which includes everyone who works here, everyone on the team, and every one of you who watched the programme.
“I’ve loved being part of it, but - and there is a but - I have decided that it is time that I stopped setting my alarm for 3:40 - sometimes when I’m feeling very rebellious 3:46 in the morning - and I’m going to be leaving the programme.
“It’s not going to be for a while, and just before anything else I wanted to thank everybody who’s watching for your loyalty and support over all these years. I have absolutely loved being part of it. I will really miss it.
“But it is time now to stop that alarm early in the morning, and thank you for watching all these years as well.”
In a BBC statement, Minchin added that there are “so many memories” that she will be taking with her after she leaves the show.
She said: “I will take so many memories with me, including reporting on the shock and anguish of the Manchester Arena bombing, starting a national conversation about menopause, and the life changing moment I took part in the Breakfast Christmas Cycling Challenge which inspired my ongoing passion for endurance sport, which I will continue when I leave.
“A big thank you to everyone who has watched and supported me, I have loved it and I will miss you all.”
When and why is she leaving - and what will she do next?
Today, Wednesday 15 September, is Minchin’s last show on BBC Breakfast.
She tweeted: “Good morning and thank you for all your love support and messages xxxx last #sofaselfie #BBCBreakfast.”
The 53-year-old presenter said that she came to her decision after realising she couldn’t face another round of winter and early morning alarms.
She said: “I find the early morning really difficult and another winter of the dark mornings was not what I wanted to do anymore.
“I just thought ‘I can’t face another winter’, because I’ve worked out over the last 20 years there’s about six weeks in the year when I go to work and it’s light, and those are the six weeks that I find the easiest.
“In December I’d taken three, four weeks off work because of an ankle operation and I had that period to realise that when I’m not getting up at 3:40am in the morning, I’m doing all sorts of things in the evening that I want to be doing – like just watching telly with my family, doing that kind of family stuff.
“So yeah, I think it was coming out of winter into this period that the decision was made.
“Also because of Covid we had holidays at home and if I’m left to my own devices in my own home, I actually go to bed about midnight and wake up about nine in the morning
“That’s the natural way my body works. So I think it made me realise that actually I particularly really struggle with the hours… I have found them really hard.”
Minchin also added that the decision making process involved “lots of in-depth discussion with friends and family”.
She said: “My children are pleased for us as a family, I think, because I always used to say to them, “Oh, do you remember before I did BBC Breakfast?” and they’d say, “Not really.” And then I realised that, actually, my daughters are 20 and 17, so of course they don’t remember life before BBC Breakfast.
“I’ve not taken my daughters to school every single day for their schooling life, so I am looking forward to school runs.
“And I’m really looking forward to things like those Sunday night dramas, which I’d love to be watching but haven’t been because I need to go to bed.
“So there’s a shared experience that I’m really looking forward to being able to have with them.
“Plus I’ve got no excuses now. I’m really looking forward to being a super taxi for the kids, which is great. And I am actually genuinely really looking forward to being able to do that!”
Minchin has previously said that after she leaves the programme that she will continue with her passion for endurance sport, and also revealed other projects that she plans to pursue.
She said: “I’ve got lots of really exciting adventures planned. I’m trying to write a book about that as well.
“And I’ll continue my podcast, which is all about the mental and physical benefits of sport and exercise.”
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What has her co-host Dan Walker said?
On the day before her last show, Minchin’s regular co-host, Dan Walker, tweeted: “I can’t believe it has come about so quickly. After 5-and-a-half years sharing a sofa with this wonderful woman... tomorrow is @louiseminchin’s last day on #BBCBreakfast. I hope you can joins us to say ‘goodbye’.”
On the day she announced her departure, Walker said: “From a personal perspective, my life will be a lot poorer without you.
“You are not only a star, you are fantastic at your job, you’re brilliant to work with but you’re also a great friend.”
At the time, Walker also tweeted: “As with everything she does… Louise announces her departure from the show with dignity and class.
“We will all miss her enormously at #BBCBreakfast. She is not only wonderful at her job… she is a great friend. Enjoy your lie-ins @louiseminchin.”
Walker posted a series of pictures of himself and Minchin, writing: “This feels like a break-up. What am I going to do without Louise?
“Thank you for all the lovely messages after an emotional morning on #BBCBreakfast - I’m sure Louise will get to read them all later. My life will be poorer without her on the sofa. She’s the best.”
Who will replace her on BBC Breakfast?
Currently there is no word about who might replace the BBC Breakfast host on the show.
There have been no announcements about any possible replacements for Minchin, although there has been plenty speculation about who could be stepping into her shoes.
Some names that have been floating around as guesses include Sally Nugent, who of course has filled in for Minchin on numerous occasions, as well as Eamonn Holmes, Alex Jones and Christine Lampard.
Dan Walker, Naga Munchetty and Charlie Sayt are among the current team of presenters on the early morning show.
BBC Breakfast editor, Richard Frediani, said: “Millions of viewers have regularly woken up with Louise for 20 years and welcomed her and BBC Breakfast into their homes.
“We will miss her brilliant journalism, good humour and boundless energy. She has been a tremendous BBC Breakfast colleague on and off screen, and will always be a friend to the team.”
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