Allstate Insurance Co. is opening its first offices in ­Massachusetts since pulling out of the market 25 years ago because of the state’s then-strict regulation of auto insurance rates.

On Monday, Allstate opened an office in North Andover­ and said it plans to open two more in the state by the end of the year. Allstate also hopes to add an unspecified number of locations in 2013, said a spokesman, Chris ­Conner.

“We haven’t had a brick-and-mortar office in Massachusetts since 1987, so this is a significant day,” Conner said.

The return of Allstate offices is another sign that the partial deregulation of auto insurance four years ago is bringing more competition to the Massachusetts market. More than a dozen other insurers also have started selling auto insurance in the state.

Allstate began selling auto insurance in Massachusetts again three years ago. But until now, Allstate has relied on agents in Connecticut, New Hampshire, Rhode Island, and other states to market products here.

Allstate’s offices will be run by independent contractors operating under the company’s brand. Allstate, of Northbrook, Ill., had about 1 percent of the state’s market in 2010, according to the Massachusetts Division of Insurance.