After running your list through an email verifier, you get back a set of status labels — Valid, Invalid, Risky, Catch-All, Unknown. Most senders know to keep the Valid emails and delete the Invalids, but the categories in between deserve more nuance. Here is what every status means and how to handle each one.
Status Overview
| Status | Meaning | Recommended Action |
|---|---|---|
| Valid | Mailbox confirmed deliverable | Send |
| Invalid | Mailbox does not exist or domain is dead | Remove immediately |
| Catch-All | Domain accepts all mail; mailbox existence unconfirmed | Segment & test cautiously |
| Disposable | Temporary/throwaway email provider | Remove |
| Role-Based | Shared inbox address (info@, admin@) | Exclude from cold outreach |
| Spam Trap | Address designed to catch senders with poor hygiene | Remove immediately |
| Unknown | Result inconclusive — could not confirm or deny | Segment & monitor |
Valid (Deliverable)
A Valid result means the verification engine confirmed the mailbox exists and is accepting mail. This is the green light to send. Keep in mind that "valid" is a point-in-time result — email addresses that were valid when verified can become invalid over time as users abandon accounts, get terminated, or change jobs.
List Decay
Even a perfectly verified list loses roughly 2% deliverability per month. Schedule re-verification every 90 days for active contact databases.
Invalid (Undeliverable)
An Invalid result means the mailbox definitively does not exist, the domain has no active mail server, or the address has a fatal syntax or DNS error. Sending to Invalid addresses generates hard bounces — the most damaging bounce type for your sender reputation.
Remove Invalids Before Every Send
Most ESPs (Mailchimp, SendGrid, Klaviyo) will suspend accounts that exceed 2% hard bounce rate. Invalid addresses are the fastest route to a suspended sending account.
Catch-All (Accept-All)
A catch-all domain is configured to accept all inbound email regardless of whether the specific mailbox exists. This means verification probes always get a positive response — making it impossible to confirm individual mailbox existence.
Catch-all results are common at company domains where IT teams want to avoid lost email from typos. Some catch-all addresses are actively monitored; others silently discard everything. For cold outreach, treat catch-all results as Risky rather than Valid — send at low volume and watch bounce rates closely.
Disposable Emails
Disposable (or temporary) email addresses come from providers like Mailinator, Guerrilla Mail, 10MinuteMail, and hundreds of other throwaway services. Users create them to sign up for things without giving their real address. These inboxes are typically deleted or abandoned within hours.
Disposable addresses almost never lead to real engagement and will generate bounces as soon as the inbox expires. Remove them from any list you intend to send to repeatedly.
Role-Based Addresses
Role-based addresses are shared inboxes not tied to an individual: info@, admin@, support@, contact@, sales@, noreply@, webmaster@. These addresses often route to groups or ticketing systems rather than a single person.
- High unsubscribe and spam complaint rates — multiple people see the email
- Often managed by IT teams who aggressively mark unsolicited email as spam
- Low engagement — role inboxes prioritize transactional email, not marketing
- Some ESPs block sending to role addresses by default
Exclude role-based addresses from cold outreach. They are appropriate only for transactional emails (receipts, support replies) sent in direct response to an action taken by that inbox.
Spam Traps
Spam traps are addresses placed on the internet by anti-spam organizations, ISPs, and blocklist operators specifically to identify senders with poor list hygiene. There are two types:
- Pristine spam traps — addresses that have never been used by a real person. If you're hitting these, you're sending to purchased lists or scraping addresses from the web.
- Recycled spam traps — old addresses that were once real but have been repurposed by providers to catch senders who never clean their lists.
Hitting Spam Traps Has Serious Consequences
A single spam trap hit can add your sending IP or domain to a blocklist, affecting all email from your organization. Remove any address flagged as a spam trap immediately and audit how it entered your list.
Unknown
An Unknown result means the verification system could not definitively confirm or deny the address. Common causes include greylisted servers, rate limiting, temporary server downtime, and provider-side verification blocking (see our article on why emails can't be verified). Unknown does not equal Invalid — treat it as inconclusive.
For opt-in lists, consider sending to Unknowns at reduced volume and monitoring bounce rates. For cold or purchased lists, err on the side of exclusion.