Whether or not you've actually filed your extra-complicated 2018 taxes, you've probably always wondered what would happen if you just DIDN'T, right?
Before we get to that, let's talk about what WON'T HAPPEN if you miss the April 15 deadline: You won't get arrested, and you won't have to wire money over the phone to avoid getting deported or foreclosed on. But there's a common tax collection scam that affects millions of people each year that makes it seem like you will.
Now that that's settled, let's get into what could happen if you miss the April 15 filing date. The tl;dr is this: Penalties for not filing/e-filing your taxes are higher than the penalties for not paying what you owe, or not paying on time. Unless you're getting a refund.
If you're owed a refund, there's no penalty for filing late. You'll just have to wait longer to get your refund.
But remember, just because you got a refund last year doesn't mean you will get one this year.
So as far as federal taxes go, it's better to be safe than sorry and to get your goods in on time.
As for state and local taxes, it's even more complicated!
In conclusion: Get thee to a tax preparer. Or get an extension ASAP.