how long does it really take for the IRS to catch up with you when you're not filing taxes?

Answer 1

Generally, the IRS has 3 years to review your tax return (they may go back up to 5 years if they suspect fraud). The three year statute of limitations starts beginning with the day you filed your tax return. If you never filed your tax return, then the statute of limitations never starts, so technically, the IRS can go after you as far back as they want. However, in practical use, they generally won't go back further than 5 years.

Answer 2

Anywhere from a few months to many years. If you don't file, they can go back as far as they want to when they do catch up to you, since the clock on statute of limitations doesn't start running until you file or they file for you.

A year or two would be common if your income was reported to them by other soures, like if you got a W-2 or 1099.

And on back taxes, you'll owe not just the original tax, but also accumulated interest and penalties.

Answer 3

If you fail to file, the SOL clock never starts ticking so they can go back to the last return filed -- decades if need be. How long it takes depends upon how long it takes for them to determine that you have unreported income. Typically that will occur in 2 or 3 years at most if any of your income has been reported by the payer.