Tops Friendly Markets has completed its purchase of four Big M grocery stores.

The stores are in Boonville, Watertown, Sandy Creek and Adams. They were independently owned by William J. Bonisteel and family.

Earlier this year, Tops acquired Big M supermarkets in Elbridge, Mexico, and Jordan.

The acquisition expands Tops’ reach into Northern and Central New York.

“We are excited about this growth opportunity for Tops, as we bring these new stores into the Tops family,” said Frank Curci, Tops Markets’ president and CEO, in a statement. “These stores are a natural addition to our current footprint.”

Three years ago, Tops bought 79 former Penn Traffic Co. stores and has spent more than $90 million to upgrade its entire chain. It recently launched a standalone brand of gourmet specialty market called Orchard Fresh.