WASHINGTON—The final health care reform legislation to be voted on by the House of Representatives this weekend dramatically scales back an excise tax on the most costly group health insurance plans and eases other new taxes on health care plans, as employers had sought.

The new legislative package, which was unveiled Thursday by House Democrats, incorporates many of the changes President Barack Obama had recommended last month to lawmakers to get the then-stalled reform drive moving again.

For employers, the most significant change involves the excise tax on the most expensive health care plans. Under the new legislative package, a 40% excise tax would not begin until 2018 and would apply to health insurance premiums exceeding $10,200 for single coverage and $27,500 for family coverage, with higher amounts—$11,850 for single coverage and $30,900 for family coverage—for plans that cover retirees and employees in certain high-risk professions. Those thresholds would rise annually to match increases in the Consumer Price Index.

In addition, dental and vision care costs would be excluded in calculating plan costs to determine if the excise tax applies, while a higher cost threshold would be permitted for employers with older workforces, among other things.

The changes are a big scale-back from the excise tax provisions in the reform bill passed by the Senate in December that drew fire from employers and organized labor. The House bill lacked comparable provisions. The cost thresholds triggering the tax would have been lower and would have started five years sooner under the Senate bill.

In all, the changes would reduce the amount of revenue generated by the tax by 80%, according to the Congressional Budget Office.

The new bill, H.R. 4782, also delays to 2013 a new $2,500 annual limit on pretax contributions to health care flexible spending accounts. The reform bills passed by the House and Senate would have imposed this new limit starting in 2011.

Following what President Obama proposed, the legislation would impose a $2,000 per employee penalty on employers with at least 50 employees that do not offer coverage to employees. The first 30 employees, though, would not be included in calculating the assessment.

In addition, employers could deny coverage to employees up to 90 days after they were hired without the assessment kicking in.

Procedurally, these changes are incorporated in a reconciliation bill that only requires a simple majority of the House and Senate to win approval.

While the House is likely to act on the bill Sunday, the Senate is not expected to vote until next week.

If the legislation wins approval, it would mark the culmination of a more-than-yearlong drive to revamp the nation’s health care delivery and financing system. Budget analysts estimate that the legislation could result in an additional 32 million Americans gaining health insurance coverage, chiefly through new health insurance premium subsidies to the lower-income uninsured.