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ObamaCare does not impose a straight-forward requirement that employers offer health insurance to workers.

If a firm with at least 50 workers has a full-time employee who is getting federally-subsided insurance through an ”exchange,” then that employer must pay a penalty for failing to offer that worker acceptable insurance on the job. (Workers that are offered qualified coverage by an employer are ineligible for the new insurance subsidies provided in the exchanges.)

The tax is scheduled to begin in 2014 and the Congressional Budget Office estimates it will bring in approximately $10 billion in annual revenue once it’s fully implemented.

For firms which do not offer insurance any insurance, have more than 50 employees, and have at least one employee receiving insurance subsidies, they must pay a tax of $2000 per subsidized employee. The individual mandate requires everyone to purchase health insurance. The tax is applied to all of a firm’s employees (after excluding the first 30), not just those that are subsidized. For example a firm with 51 employees would pay $42,000 in new annual taxes, and an additional $2,000 tax for every new hire.

For firms that do offer insurance, the penalty is the lesser of $2,000 for every employee (after exempting the first 30) or $3,000) for every employee receiving a subsidy.

You would have to offer the the insurance,

and pay some part of the premium, however

the payments would be deductable,

and you would receive a tax benefit as well,

The law is vague but not more than 50%

The law states the above,

Employers with more than ten employees will be required to provide employees with health insurance, and make a "fair and reasonable" contribution to the cost. Employers who satisfy both of these requirements are called "contributing employers." What constitutes a fair and reasonable contribution amount is to be interpreted by the Division of Health Care Finance and Policy. Regulatory guidance will prove critical for employers wondering whether they must contribute 10 percent, 25 percent, 50 percent or some other amount in order to satisfy their obligation. This contribution level has not yet been determined and should be closely monitored.

Employers who do not comply with this provision will pay a "Fair Share Contribution." The amount of the contribution will vary, but it is capped at $295 per employee. The Fair Share Contribution is designed to reimburse the State for the free health care provided to employees whose employers do not offer insurance (M.G.L. ch. 149 § 187).

Another charge assessed to employers is the "Free Rider Surcharge," imposed where the employer has more than 10 employees, fails to provide health insurance, and whose employees, as a result, depend on free health care. This charge does not occur automatically, but only when (1) an employee obtains free health care at a medical facility more than three times in a year, or (2) employees in the aggregate receive free care on at least five occasions in a year.

What you will need to do is speak to your accountant at the time the law begins and see if it is cheaper to not provide any coverage, as the employees would be able to get subsidized medical insurance on their own, and pay much less