What are the main types (pristine, recycled, typo)?

Each type of spam trap exposes a different gap in how you acquired or maintained your list. Understanding which kind you're dealing with tells you where the problem actually is.

Pristine traps

Pristine traps are addresses that were never real. They've never belonged to a person, never been used to sign up for anything legitimate. They're planted in places where only scrapers or bulk harvesters would find them: hidden in webpage source code, buried in public databases, or distributed in files that circulate in data-broker markets.

If you mail a pristine trap, the signal is unambiguous: you either bought a list, scraped addresses, or used a data source that did. There's no scenario where a real subscriber voluntarily gave you an address that was specifically created as a trap. Blocklists weight pristine trap hits heavily precisely because intent is hard to argue away.

Recycled traps

Recycled traps were once real. An ISP or domain operator had an active inbox at that address, but it went abandoned and unengaged long enough that it was repurposed for trap activity. The address was real. It's just not anymore, and hitting one reveals that you're holding onto old, unhygienic contacts you should have removed.

But the recycling window varies. ISPs don't announce exactly when an address transitions from "abandoned" to "trap," but addresses that haven't engaged in 18-24 months are commonly considered at risk. Recycled traps are the most common type for senders who have reasonable acquisition practices but poor list maintenance. If you're hitting recycled traps, the question to ask is: how long have these addresses been inactive, and what's your suppression policy for non-engagers?

Typo traps

Typo traps sit at domains that are common misspellings of major email providers: gmal.com, gnail.com, yaho.com, hotmai.com. Organizations monitoring sender reputation register these misspelled domains and run mail servers on them. When email arrives, they log who sent it.

Hitting a typo trap means someone typed their email address wrong at your signup form and you didn't catch it. It's a data quality issue at the point of acquisition. Since email to a misspelled domain can never reach the person who typed it, there's also no way they confirmed their signup or ever engaged. You've been holding an unreachable address, and now it's working against your reputation.

Now the fix for typo traps is to validate addresses at input, ideally catching domain-level misspellings in real time. Email validation at the signup stage is the most direct prevention. Double opt-in also helps: a subscriber who typed a wrong address won't receive the confirmation email and won't complete the opt-in, which keeps the bad address off your active list.

The pattern each type reveals

Think of the three types as diagnostic signals. Pristine traps point toward acquisition source problems. Recycled traps point toward list maintenance problems. Typo traps point toward signup form problems. If you know which type you're hitting, you know where to fix things first.