A New Hampshire contracting company will pay a $75,000 fine to Massachusetts after the Office of Campaign and Political Finance determined it illegally provided corporate funds to employees for donations to the campaigns of Boston Mayor Martin Walsh and a city councilor.

In violation of Massachusetts campaign finance law, employees of Select Demo Services LLC donated a total of $21,000 from their personal accounts for which they had been paid by the company, OCPF announced Tuesday.

Twenty employees or affiliated individuals with the specialty contracting firm based in Salem, New Hampshire each made $1,000 contributions to Walsh’s campaign in December 2019, campaign finance regulators found.

Donations made by personal check were dated on or about Dec. 4, 2019. Select Demo had issued $1,000 checks to each of those workers on or about Dec. 3, 2019, according to the investigation.

Around Sept. 19, 2019, an employee also donated $1,000 to Boston City Councillor Michael Flaherty’s campaign, money the company said it also provided.

In every instance, the employees donated to Walsh and Flaherty “at the request or suggestion” of company president Ryan Denver and were told they could seek reimbursement from the company, according to a disposition agreement signed by Denver and OCPF Director Pro Tem Michael Sullivan.

Workers agreed to make the contributions voluntarily and were not pressured to do so.

Massachusetts campaign finance law prohibits corporations from directly or indirectly donating to a political candidate and bans contributors from disguising the “true origin” of the funds.

Denver, whose company has about $125 million in annual sales and an office in Boston, told regulators that he was unaware of those provisions when he asked his employees to contribute to Walsh and Flaherty’s campaigns.

“Whoever contributed funds ultimately derived from Select Demo did so willingly, voluntarily, and without malintent,” OCPF wrote in a section of the agreement outlining Denver’s position. “Denver only wanted to support candidates whom he believed shared similar values. Neither Denver nor Select Demo has ever asked for or received anything in exchange for supporting the particular candidates; indeed, Select Demo has never directly bid for or performed work for the City of Boston.”

OCPF said it started its investigation following a “routine review” of campaign finance reports filed by Walsh and Flaherty’s committees. Regulators examined bank records of the donors and other information.

The two campaigns were not aware of the violations behind the contributions, according to OCPF. Neither Walsh nor Flaherty’s offices responded to requests for comment Tuesday.

Under the disposition agreement with OCPF, Select Demo will pay a $75,000 civil forfeiture into the Massachusetts general fund and implement a campaign finance law training program for its employees.

The office agreed not to refer Select Demo or Denver to the attorney general or any other governmental agency for the specific violations laid out in the agreement.

Walsh and Flaherty will need to disgorge the $21,000 they received in prohibited funds. An OCPF spokesperson said that money will also go to the general fund, pushing the total amount added as a result of the settlement to $96,000.

OCPF records show a range of other donations by Select Demo employees that were not part of the violations, including past support of Walsh and contributions to Gov. Charlie Baker’s during his 2018 re-election campaign.