In its latest revision, the administration has pushed back a key deadline for some small employers. (Mike Segar/REUTERS)

The Obama administration on Monday released the final regulations concerning what is commonly known as the employer mandate provision of the health care law, giving some mid-sized businesses an additional year before they are required to provide sufficient coverage to their workers.

One of the most controversial parts of the legislation within the business community, the rules in question require businesses with at least 50 employees to offer health plans that meet new minimum coverage and affordability standards in the law. If not, the company will be required to pay a potentially steep fine — or, as the administration refers to it, an “employer responsibility payment.”

Originally, the rules were slated to take effect last month; however, late last year, the administration announced it would delay enforcement until January 2015.

In the final regulations published Monday, Internal Revenue Service and Treasury Department officials established three separate timetables for business owners, no longer spliting employers into only “large” or “small.”

Here’s what employers need to know.

For companies with 100 or more employees: These companies will be required to start reporting information about the firm’s insurance plan starting next year, and in order to avoid a fine, the company must cover 70 percent of its full-time workers.

That gives large employers a little bit of breathing room the first year. In 2016, companies will be subject to the penalties if they cover less than 95 percent of their full-time employees.

For companies with between 50 and 99 employees: These mid-sized companies get an even bigger break during the first year, according to the rules released Monday. While they too must begin reporting details about their insurance coverage to the federal government in 2015, companies that fall between 50 and 99 workers will not face any enforcement fines for another year, essentially delaying the mandate again, this time until 2016.

At that point, they too will be required to cover 95 percent of their workers in order to avoid the penalty.

For companies with 50 or fewer employees: Under the health care law, businesses that fall under the 50-worker threshold are not required to provide coverage or file any additional paperwork to the government under the employer responsibility clause of the Affordable Care Act.

That exempts the vast majority of U.S. companies from the rules altogether, though many have warned that it may create a disincentive to companies to expand beyond the 50-employee threshold. Other worry it could also encourage firms to move full-time workers to part-time positions, to avoid tripping the 50-worker limit.

Related: How to calculate your number of full-time workers under the ACA

In addition, regulators provided some clarification on additional questions that have hovered over the business community:

• Volunteer hours contributed to government or other-tax exempt entities will not factor into the equation for determining that individual’s full-time status.

• Seasonal employees for whom the typical employment period is six months or less will not generally be considered full-time employees.

• Employers will be able to use a simplified “look back” method that takes into account hours worked by seasonal and part-time employees last year to determine whether they should be considered full-time for the current year.

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