By George P. Hassett

Somerville’s state delegation last week unanimously supported Gov. Deval Patrick’s bill closing corporate tax loopholes, reducing the corporate tax rate, and clarifying the corporate tax code. The bill was passed by both the Senate and House of Representatives.

The bill originated to close loopholes that large corporations have used in the past to avoid paying state income taxes. These loopholes included allowing corporations to shift profits out-of-state and to define the corporation differently on state and federal tax forms.

In a statement, Patrick said the bill will help Massachusetts businesses retain their competitive edge, while generating hundreds of millions of dollars in new revenue to sustain vital government services over the next few years.

In the first two years the changes are implemented, the state is expected to receive an additional $681 million in revenue, according to independent studies.

“These loopholes have shifted the tax burden onto local small businesses that cannot take advantage of them and onto Massachusetts working families, who have seen their property taxes rise year after year,” said Representative Carl Sciortino, D-Medford, in a statement.

He said the bill ensures that multi-state corporations “pay their fair share.”

State Sen. Patricia D. Jehlen, D-Somerville, said the bill will also save small businesses money as the tax rate is reduced from 9.5 percent to 8.5 percent.

“This legislation modernizes our tax code and makes it more fair for all businesses,” she said.

The original corporate tax bill that passed in the House reduced the corporate tax rate to 7.5 percent over three years, while the Senate version of the bill went down to 8 percent. In the end, the Senate’s version of the tax cut was adopted.

“This bill is a win-win for the hard-working businesses in Massachusetts,” said State Representative Tim Toomey, D-Cambridge. “The large corporations using this loophole to gain an unfair advantage will be brought back into the system on equal footing, and the ones playing by the rules will get a tax break.”

The loophole closures will go into effect beginning January 1. The tax cuts will be phased in over three years beginning January 1, 2010.