Millions of Americans are facing hidden tax surcharges on their insurance premiums under President Barack Obama's healthcare law as well as new health-related taxes on their income tax bills, the New York Post reports.

Some health insurance companies are not informing patients about the Obamacare taxes, instead deciding to quietly pass them on to its customers. But Blue Cross Blue Shield of Alabama has revealed the taxes on its bills with a separate line item for "Affordable Care Act Fees and Taxes."

According to the report quoting Kaiser Health News, the surprise taxes on one customer's bill was $23.14 a month, or $277.68 annually, which increased the monthly premium from $322.26 to $345.40 for that person.

The two percent tax on customers for every health plan is expected to net about $8 billion for the government in 2014 and increase to $14.3 billion in 2018.

There's also a $2 fee per policy that goes into a new medical research trust fund called the Patient Centered Outcomes Research Institute. As for insurers, they have to pay a 3.5 percent user fee to sell medical plans on the HealthCare.gov website.

The Post says Obamacare supporters may point out that federal subsidies for low-income families will cover the taxes and pay a large part of the actual premiums.

However, there's also another Obamacare tax that people don't know about. Americans who have to buy medical devices like pacemakers, stents and prosthetic limbs will have to fork over a 2.3 percent medical device tax.

Another hidden expense will affect Americans who have to pay out a large share of their annual income for medical costs. Currently, Americans are allowed to deduct medical expenses higher than 7.5 percent of their incomes. But that figure leaps to 10 percent under Obamacare, which will cost taxpayers $15 billion over 10 years, says the Post.

For some Americans there will also be an increase in Medicare tax. Individuals earning more than $200,000 a year and families earning more than $250,000 will have 0.9 percent surtax over the existing 1.45 percent Medicare payroll tax.

Furthermore, these high-earning Americans will also pay an extra 3.8 percent Medicare tax on unearned income, such as investment dividends, rental income and capital gains, adds the Post.