The high street restaurant will be weighted towards grab-and-go and has been designed to offer a 'digital-first' experience with kiosks for digital ordering and payments.
"We are delighted to be opening our first Leon in Bath, a city so loved by locals and tourists alike," says Glenn Edwards, Leon's managing director.
"Celebrated as the original home of wellbeing we are delighted to bring our naturally fast food to Bath and continue with our mission to help even more people eat well, live well and be kind to the planet."
The Bath opening represents yet more expansion outside of London for Leon. The group, which operates more than 80 UK restaurants that are primarily concentrated in the capital, was acquired by forecourt retailer and fast food operator EG Group in April 2021 in a deal reported to be worth up to £100m.
Since then Leon has been targeting an accelerated UK expansion, with EG Group previously saying it would aim to open 20 new sites per year.
At 160.8sq/m, the Bath restaurant will feature 16 internal seats for guests to dine in, with a further eight seats available outside.
Diners will also be able to order food for delivery via local partners such as Deliveroo, Uber and Just Eat.