Belmont Savings Bank has formed a partnership with Shaw’s Supermarket to open an in-store branch in its Waltham location.

The new in-store branch at 1070 Lexington St is expected to open May 1.

This branch, which represents Belmont’s first expansion in a decade, will be a full-service bank branch and the bank’s first Waltham branch.

"We are proud to be partnering with Shaw’s Supermarket, and bringing The Belmont Savings Platinum Blue Relationship Banking program to Waltham," said Bob Mahoney, president and chief executive officer of Belmont Savings Bank. "In today’s world, convenience and technology matters, and that is why we’ve been able to grow – we combine local service with all the same online banking of a large bank, allowing our customers to bank with us when and where it works for them."

The Waltham announcement continues the bank’s planned expansion of its branch network, bringing the total number of branches in the Belmont-Watertown-Waltham area to five. Bank officials pointed to the in-store branch as the next logical step for the bank, according to a statement.

"A key component of Belmont Savings Bank’s growth has been its partnerships with community businesses. In doing our first partnership with Shaw’s, we will be able to reach to 16,000 potential prospects each week," said Hal Tovin, chief operating office of Belmont Savings Bank and one of the pioneers behind the in-store branch program during his time at Citizens Bank. "We are very excited at the prospect of being able to expand our footprint to the Waltham marketplace."