Dorothy Coutts, 62, launched her store, C&M, in 1984 when the shopping street looked vastly different to today.
The mother-of-two would travel across the north of England to collect stock for the shop, which mostly dealt in “seconds” from Marks & Spencer factories or items with minor flaws.
Later, she bought from a clothing wholesaler but continued to maintain a successful high street business for almost three decades before deciding to retire and close the shop.
Mrs Coutts, who was born and bred in Portobello, plans to keep active in retirement and has vowed to go on plenty of long walks.
The veteran retailer said she would miss the hundreds of loyal customers who visited her store over the years. “It will be very sad leaving the shop but I will quite enjoy my retirement,” she said.
“It will be the customers that I miss the most and all their stories and the buzz of the place. They used to come down from all over Edinburgh to shop and have a chit-chat.
“When I started I didn’t really have an interest in clothes and just thought I would give it a try.
“My husband, John, did up the property because he was a joiner and a builder.
“We thought ‘why not give it a try?’ but I certainly didn’t think it would last as long as it did.”
Mrs Coutts, who attended Portobello High School, employs several staff, one of whom has worked on High Street for 40 years.
It is not yet known what type of retail outlet will open in place of C&M.
“I will miss being part of the High Street but there have been a lot of changes to the shops over the years,” she said. “There were never any charity shops when I first opened, there used to be shoe shops, grocers, and bakers and all the individual shops but it doesn’t seem to be like that any more.
“We used to go down south and pick the stock and used to have to go to different factories that made for M&S.
“After the first four years at Marks & Spencers, stuff dried up because all the clothes were being made in other countries so many of the factories stopped doing that, then I started having to go to wholesalers.
“We would probably go about once every two months.
“Now you can order everything online but I’m still using carbon paper, hence the reason I’m retiring,” joked Mrs Coutts.
“I’m just going to bow out gracefully.”
She added: “Portobello is a really nice place, with really nice people. It means everything to me.
“I really enjoy living here and I want to thank all my customers, past and present, for their loyal support over the years.”