(Bloomberg Business) -- Tax season isn't supposed to be fun. But if your civic duty feels extra unpleasant this year, you're not imagining things. Here are four reasons this tax season really is the worst.

OBAMACARE CREATED A NEW HASSLE

About 7 million people bought insurance through an Obamacare marketplace and received subsidies, which were based on their estimated incomes. More than half of those folks underestimated their incomes — and now they owe. According to H&R Block, their refunds were cut by an average of 17%, or $530. The one-third that overestimated their 2014 pay are seeing their refunds rise $365.

Then there are those who refused to buy insurance, despite the law’s mandate. It's hard to say how big this group is — about 11% of Americans didn't have health insurance last year, but many of them may qualify for hardship exemptions. Those that don't are in violation of the law and face an average penalty of $172.

FRAUD IS GROWING

This year, for the first time, a critical mass of states have reported a wave of suspicious state tax returns. Criminals were using tax prep software to claim other people’s tax returns, prompting a handful of states to issue broad alerts. Minnesota even temporarily stopped accepting tax returns from Turbotax, the online tax software that appears to be tax fraudsters' favorite target.

As a result of the fraud, some states are slowing down their processing of returns. Ohio, for example, says it’s taking up to three times as long: electronic returns that took five or six business days are now taking more than three weeks to process. Paper returns can take a full month, double what they took last year.The IRS is broke Adjusted for inflation, the IRS’s budget is down 17% since 2010. With less money and staff, theIRS must handle a growing workload each year — 100 million phone calls, 10 million mailed inquiries, 160 million returns and counting. Last year, more than one out of three phone calls to the agency went unanswered, according to the Taxpayer Advocate Service, and only half of mail was handled in a timely manner. No one expects it to be any better this year.

YOU'RE A PROCRASTINATOR

The IRS opened for tax filing 11 days earlier this year, but Americans have yet to get off their collective duff. Three out of five taxpayers still haven't filed; at the end of February, the agency had received 335,000 fewer tax returns than it had at the same time last year.

Waiting until the last minute isn't necessarily harmless. It gives criminals more time to use your social security number to file a tax return on your behalf. And, starting in right around now, many tax prep services start raising their prices. Those who procrastinate all the way until early April pay the most.

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