National Australia Bank will spend $2 million combining its Warrnambool services at Koroit Street.
Next week the branch will temporarily move to Kepler Street, where its business bank facilities are currently located, while the renovations take place.
When those renovations are completed in late September, the Kepler Street site will then close.
NAB retail customer executive Helen Adamson said the new-look Koroit Street branch would include a third Smart ATM.
"Once the renovation work is complete, our branch and business banking centre will both be conveniently located on Koroit street," Ms Adamson said. "We love being part of the Warrnambool community and thank our customers and the community for their patience as we carry out the renovations."
In March, NAB group chief executive Philip Chronican committed to keeping eight south-west bank branches open until at least January 2021, as part of a national promise of no branch closures in regional and rural communities.
NAB closed its Port Fairy and Casterton branches in August last year.
The Koroit Street branch will temporarily close this Friday and open at the Kepler Street site from July 8 at 10.30am.
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