Are error fares real? Yes, they happen: an airline or one of its partners fat-fingers a price, drops a currency conversion, or leaves a fuel surcharge off, and for a few hours a flight that should cost $1,200 sells for $180. They're real. They're also rare, and most of the "error fares" people get excited about are just ordinary good deals wearing a dramatic name.
The confusion is understandable. A genuinely low fare and a pricing mistake look identical on the search results page. Both are cheap. The difference is that one is a price the airline meant to sell and the other is one it didn't, and that gap is exactly where the risk lives.
How to tell a real mistake from a good deal
A normal good fare is cheaper than usual but still in the realm of sanity: a route that's typically $600 showing up at $380 during a quiet season. That's not an error. That's the fare doing what fares do, which is swing around more than most people expect.
A real error fare is the one that makes you laugh. Business class across an ocean for the price of a domestic hop. A long-haul return for less than the taxes alone should be. When the number is off by a factor, not a fraction, you're probably looking at a mistake. And because it's a mistake, the airline may quietly cancel it, honor it, or refund you and pretend it never happened. There's no rule that forces them to fly you for a price they entered by accident.
What to do if you find one
If you decide to book one, book only the flight, and wait. Don't reserve the hotel, don't buy the tickets to the thing you're flying out for, and don't tell yourself the trip is real until the airline has left the booking alone for a week or two. Pay with a card that makes refunds painless. Assume it might vanish, and you'll be fine either way.
For what it's worth, chasing error fares is a hobby, not a plan. It means watching dozens of routes you don't care about on the off chance one breaks. The three fares we send each day are the opposite bet: real prices, on the routes you actually want, that the airline fully intends to sell. If one of those happens to be a jaw-dropper, a good fare goes fast, so it's worth booking before it moves. It just won't disappear on you the next morning.