[throwawayboise]

It's not like an honest mistake is the end of the world. I've made tax mistakes. You get a letter from the IRS, with the amount you owe or are due back, and you settle up. There are no draconian penalties or full audits unless they suspect intentional fraud.

[kstrauser]

They're usually shockingly pleasant to deal with, too. Having owned a couple of small businesses over the years, our taxes can get complex. There were a couple of times where the IRS had questions about our filed returns, and the clerks we dealt with have always been genuinely nice, helpful to work with, and authorized to exercise decent human judgment.

Them: It says here you spent $X on healthcare expenses.

Me: I've got 4 kids. I always hit my deductible.

Them, literally laughing: Yeah, kids are expensive. OK, moving on...

[bombcar]

The IRS will even send you "you screwed up and paid us too much, you forgot X" letters at times.

What they can't do for you is know about deductions sometimes.

[ceejayoz]

I was once on an IRS payment plan, and a) the interest rate was remarkably low and b) the folks I talked to when I needed to adjust it were the nicest customer service reps I think I've ever encountered.

[rurp]

Yep, that has been my experience. I got pretty freaked out once when I received a large packet from the IRS in the mail. Turns out I forgot to report a stock sale and just owed them a few hundred bucks. The only penalty was having to pay interest on the amount at a rate that was a little high but not egregious.