The U.S. Senate passed legislation early Saturday morning that would lower taxes for businesses while potentially raising taxes on many individuals, and the association community is divided about whether the bill would aid or harm the economy.

Proponents of the legislation include many groups that represent businesses large and small, such as the U.S. Chamber of Commerce, National Retail Federation and National Federation of Independent Business. But a wide range of groups also have spoken against the legislation because it would eliminate or reduce many tax breaks used by individuals while also ending government penalties for not carrying health insurance.

The American Hospital Association is "disappointed that the tax legislation passed with a provision that would eliminate the individual mandate, which would result in the loss of health insurance coverage for millions of Americans," CEO Rick Pollack said.

The Senate tax overhaul bill contains significant differences from the House version passed in November. Both bills would lower the corporate tax rate, but the Senate bill eliminates the individual mandate while the House bill does not. The Senate bill also preserves tax breaks for mortgage interest, college tuition and medical expenses.

Both bills now head to conference committee to hammer out a final version, which both the House and Senate must approve.

Most individuals will receive tax breaks the first year either bill goes into effect, but many people could eventually pay more in taxes depending on their circumstances. Households that currently itemize their deductions could pay more in taxes under both versions, while the Senate bill would ultimately increase taxes for households with incomes less than $75,000, according to an analyses of the legislation by Congress's Joint Committee on Taxation.

The potential effects on individuals are why many groups oppose both versions of the GOP tax plan even if those same groups are otherwise on board with lowering taxes.

"Realtors support tax cuts when done in a fiscally responsible way; while there are some winners in this legislation, millions of middle-class homeowners would see very limited benefits, and many will even see a tax increase," said Elizabeth Mendenhall, president of the National Association of Realtors.

The National Association of Home Builders was one of the earliest and most vocal opponents of the House bill, primarily because the legislation cut the mortgage interest deduction in half while capping local property deductions at $10,000. The Senate version leaves the mortgage interest deduction untouched but eliminates the property tax deduction.

NAHB has been relatively silent about the Senate bill. As to the House version, association CEO Jerry Howard told CNBC Friday that he was more upbeat about tax talks after meeting with Republican leaders in the chamber.

"I'm not saying we're in support of the bill yet, but we're in a much better place than we have been," Howard told the network. "They're very interested in our ideas." http://cnb.cx/2A2r3pm

Both versions of the plan still face opposition from groups representing higher education, hospitals and doctors, scientists and professional services companies like architects. The plan's' supporters are business groups that have long argued that lowering the corporate tax rate would boost the U.S. economy.

"History has been made again, and our nation is now on the verge of seeing the biggest, boldest tax reform in more than three decades," said Jay Timmons, CEO of the National Association of Manufacturers.

As for a direct effect on associations, both versions of the GOP plan would create a 20 percent excise tax on nonprofits for executive salaries exceeding $1 million, although only for the five top-paid staff. The tax could generate $30 million in one year in tax revenue if applied to the most recent salaries disclosed in IRS Form 990s, according to an analysis of organizations tracked by CEO Update.

MORE CEO DATELINE

• Oil groups blast EPA decision to uphold ethanol mandate
• Massage associations dispute report of widespread industry sex trafficking
• Government data shows decline in international travel to U.S.
• Oil association says STEM graduates have best prospects in industry
• Former AIAA CEO dies