Associated British Foods' Primark clothing business will invest over £100 million (€117.2 million) in its UK store estate in 2024, opening three new outlets and extending others, the company said.
It said the total includes more than £75 million (€87.9 million) of new investment, building on plans it announced in November 2022.
Primark's investment shows the continuing importance of physical stores to retailers despite the rise of online shopping over the last two decades.
Primark does not offer home delivery but is trialing a click and collect service.
It said a new store will open in Bury St Edmunds, eastern England next month, followed by Teesside Park in north east England and Glasgow Fort in Scotland later in the year.
Alongside these, Primark will open some of its biggest ever store extensions across the country. It said almost 700 new jobs will be created in the UK this year.
Two more UK store openings have also been confirmed for 2025.
Primark currently trades from over 400 stores across 16 countries in Europe and the United States. It is targeting 530 stores by the end of 2026.
Shares in AB Foods, which also owns major sugar, grocery, agriculture and ingredients businesses, were up 1% in morning trading.
Like-for-like sales rose 2.1% in the 16 weeks to 6 January, its fiscal first quarter, a slowdown from growth of 8% in the previous quarter, while total sales were up 7.9% over the period.