BOSTON (State House News Service) - A roughly $1 billion tax relief package that has been under debate for some 20 months sailed through the House on Wednesday with a single dissenting vote and lots of self-congratulatory pats on the back.

Representatives voted 155-1 to accept a conference committee report that was filed a day earlier, which would roll out a bevy of tax breaks, credits and reforms while reshaping a pair of voter-approved tax laws.

Rep. Mike Connolly, a Cambridge Democrat who opposed the original tax policy legislation the House approved in April, cast the only no vote.

Several Democrats and Republicans spoke in favor of the measure before approving it Wednesday, describing it as a way to address both affordability concerns that many residents face and growing worries that Massachusetts is not as competitive as other states.

Connolly was the only lawmaker who voiced opposition to the bill during Wednesday's session, which puts tax relief even closer to Gov. Maura Healey's desk after more than a year and a half of stops, starts and deliberations that mostly took place behind closed doors.

"Getting here today was by no means a small accomplishment. It has been a long time," Rep. Aaron Michlewitz, the House's lead negotiator on the final package, said during Wednesday's session. "It took a lot of collaboration and hard work, but I believe the results that are with you today are necessary for our commonwealth at this time."

"Even though we had some bumps and bruises along the way, we got this done, and we're hopefully going to see it signed by the governor," he later added.

The Senate is expected to accept the compromise tax bill Thursday and tax relief has been a priority for Gov. Maura Healey dating back to her campaign for governor.

Democrats estimate the bill (H 4104) would provide about $561 million in relief this fiscal year and more than $1 billion annually starting in fiscal year 2027 once all of its provisions are fully implemented.

Senate President Karen Spilka on Tuesday pitched the accord as "the largest bipartisan legislative tax relief proposal in over a generation."

The package combines a range of reforms aimed at low- and middle-income taxpayers, especially a revised and expanded credit for parents and caregivers, with changes backed by business groups that supporters say will make Massachusetts a more competitive, compelling option compared to other states.

It would reduce the tax rate on short-term capital gains from 12 percent to 8.5 percent, effectively double the threshold at which the estate tax kicks in, and simplify the way tax bills are calculated for multi-state companies in Massachusetts.

The measure also features several expanded tax credits and incentives designed to spur more production of housing.

"The tax package we are taking up shows compassion because it gives relief to those of our constituents that need it the most," Michlewitz said. "It shows responsiveness to today's economic trends. It helps make the commonwealth more competitive and move forward in a positive sense."

Connolly, who in the spring had argued the original House bill contained too many pieces that would "overwhelmingly benefit big corporations and the very wealthy," said Wednesday the updated legislation had been "significantly improved" during negotiations.

But in his mind, it still wasn't enough.

"There are several elements of the bill that I enthusiastically support, and yet, as I stand here today, I cannot bring myself to support the full price tag of $1.1 billion once fully implemented, not after we just spent a decade working to pass the Fair Share amendment to gain desperately needed revenue for our programs in our communities," Connolly said, referring to the state's new surtax on high-earners that is expected to generate about $1 billion in tax revenue a year. "When I speak with constituents of the Cambridge and Somerville district that I represent, they tell me the most pressing issues on their minds are the affordable housing emergency, the ongoing MBTA disaster and the escalating threat of climate change."

The final margin of passage was better than during the springtime debate: Democrat Reps. Erika Uyterhoeven of Somerville and Danillo Sena of Acton voted against the House's original bill in April and in favor of the conference committee report on Wednesday.

Several of the package's pieces, such a $1,000 increase to the rental deduction cap and a doubled maximum senior circuit breaker tax credit, mirror what the Legislature approved last year before the sudden revelation that state government owed taxpayers nearly $3 billion spooked top Democrats into retreating from the idea.

The voter-approved law known as Chapter 62F caps the amount of tax revenue state government can haul in each year. Any collections above the limit must be returned to taxpayers, as was the case last year when Massachusetts hit the cap for only the second time in the law's existence.

If state government were to trigger that cap again, the response would be significantly different under the latest legislation.

The compromise tax relief bill replaces the existing 62F framework, which requires taxpayers to be repaid in proportion to the amount of taxes they owed, with an equal payment for every eligible recipient regardless of how much they paid.

Michlewitz said it would be a "fairer and more equitable payment distribution should this law ever be triggered again."

During the original House debate in April, Republicans unsuccessfully fought to spike that language, arguing at the time that the change would violate the will of the voters who first enacted the law.

No one in the minority party raised any vocal concerns Wednesday about the topic before approving the compromise bill.

A pair of Republicans, Rep. Michael Soter of Bellingham and Rep. Steven Howitt of Seekonk, voiced their support for the tax package before it cruised to passage, though Soter acknowledged the changes "aren't perfect."

Soter, who served on the conference committee that agreed to the compromise, said he believes the "biggest change" is the reform to the estate tax. The bill would deploy a uniform estate tax credit of $99,600, which authors say would effectively double the threshold at which the tax kicks in from $1 million to $2 million while eliminating the "cliff effect" that currently subjects an entire estate to taxation rather than just the amount above the threshold.

"When our constituents pass on their hard-earned assets to their loved ones, they won't face the same financial strain after their death," Soter said. "It's about making sure that their legacy is preserved and passed on to the next generation."

The legislation also takes aim at the new surtax on income above $1 million, which won approval at the ballot box in November.

It would require all taxpayers who file a joint return at the federal level to do the same at the state level, effectively ensuring the surtax applies to married couples who earn more than $1 million together but might not trigger the levy filing as separate individuals.

Michlewitz said the new language would "close a loophole" in the ballot law.

"This change will take effect next year, and could generate between $200 and $600 million annually," he said. "We'll see how that plays out."

Written By Chris Lisinski/SHNS

[Sam Drysdale contributed reporting.]