Email server settings

Cox.net SMTP settings after the move to Yahoo

Q: What are the cox.net SMTP settings?

Since cox.net email moved to Yahoo: smtp.mail.yahoo.com, port 465 with SSL/TLS or port 587 with STARTTLS, authentication on, user name = your full cox.net address, password = a Yahoo app password.

Q: What are the Cox IMAP settings?

imap.mail.yahoo.com, port 993, SSL/TLS, with your full cox.net address and a Yahoo app password. POP3 is pop.mail.yahoo.com on port 995.

Cox no longer runs its own email: Cox says it has completed its transition to Yahoo Mail. The cox.net SMTP settings are therefore Yahoo’s: smtp.mail.yahoo.com, port 465 with SSL/TLS or 587 with STARTTLS, incoming imap.mail.yahoo.com on port 993, your full cox.net address as the user name and a Yahoo app password.

Last checked October 10, 2026, against Cox’s and Yahoo’s own help pages.

Cox.net SMTP, IMAP and POP3 servers (Yahoo Mail)

Server, port and securityServer	Port and security
IMAP · incomingimap.mail.yahoo.com993 · SSL/TLS	993SSL/TLS
POP3 · incomingpop.mail.yahoo.com995 · SSL/TLS	995SSL/TLS
SMTP · outgoingsmtp.mail.yahoo.com465 · SSL/TLS	465SSL/TLS
SMTP · outgoingsmtp.mail.yahoo.com587 · STARTTLS	587STARTTLS

Sign-in: Full cox.net address + Yahoo app password

User name: your full Cox address, for example jane.doe@cox.net; the password is a Yahoo app password.

Cox email settings after the Yahoo transition

Cox’s help center says Cox email customers “will now use Yahoo Mail to access their existing cox.net email accounts”, that “Yahoo will manage all email-related support”, and that Cox “will no longer offer or support email services” (Cox: cox.net email transitioning to Yahoo, Completing the transition).

Your address stays. You keep using your cox.net address; messages, folders, calendar and contacts moved to Yahoo.
Mail apps need new settings. Cox: the settings for a third-party email client “will need to be created on your part to reflect the new Yahoo settings”. If your app still points at Cox’s old servers, replace them with the Yahoo servers above.
The values come from Yahoo’s article Update your cox.net email settings in Outlook, Mail on Mac and other third-party email clients: IMAP imap.mail.yahoo.com (993, SSL/TLS), POP pop.mail.yahoo.com (995, SSL/TLS), SMTP smtp.mail.yahoo.com (465 with SSL/TLS in Yahoo’s Outlook steps, 587 with TLS/SSL in its Mac steps, authentication on).
No new accounts. As of August 15, 2019, Cox no longer lets customers create new Cox Email accounts (Cox).

The servers are the same as for any Yahoo address: see Yahoo Mail IMAP settings.

Yahoo’s cox.net article starts with the app password: third-party mail apps need one instead of your regular password.

Sign in to Yahoo’s Account Security page with your full cox.net address.
Find App Passwords and choose to generate one.
Name the app (for example “Outlook”) and generate the password.
Copy it into the password field of your mail app, for incoming and outgoing mail.

For two-step verification, Cox points to Yahoo’s Security Center.

Accept Yahoo’s terms first. Until you sign in once at Yahoo Mail and accept the Terms of Service, you can’t send or receive, even if a mail app still shows your old messages.

Cox email settings for Outlook, Mac Mail and iPhone

Outlook: remove the old Cox server settings, add the account as IMAP with imap.mail.yahoo.com (993, SSL/TLS) and smtp.mail.yahoo.com. Yahoo’s Outlook steps use port 465 with SSL.
Mac Mail: Yahoo’s steps use smtp.mail.yahoo.com on port 587; incoming stays imap.mail.yahoo.com on 993.
iPhone, iPad and Android: add an IMAP account with the same values and the app password, or sign in to the Yahoo Mail app with your full cox.net address.
Web: sign in at mail.yahoo.com with your full cox.net address and the new password you created during the move.

Common cox.net email problems

Error or symptom	Fix
Old messages are visible, but nothing new arrives or sends	You haven’t accepted Yahoo’s Terms of Service yet. Sign in at `mail.yahoo.com` once with your cox.net address and accept them.
Password rejected in Outlook or Mac Mail	The app uses your regular password. Create a Yahoo app password and enter it instead.
The app still connects to Cox servers	Edit the incoming and outgoing servers to `imap.mail.yahoo.com` and `smtp.mail.yahoo.com`, or remove the account and add it again.
Forgotten password	Before the move: Cox’s email login page. After the move: Yahoo account recovery.
A deleted cox.net address should come back	Cox: once an account has moved to Yahoo Mail, former Cox addresses “cannot be reactivated through Cox.”

More Yahoo-side fixes (app passwords, 553 errors, outdated apps) are on the Yahoo Mail IMAP settings page. For bounces, see the SMTP error codes.

Is @cox.net still a valid email domain?

Yes, for existing accounts. cox.net addresses keep working on Yahoo Mail, but nobody has been able to create a new one since August 15, 2019, and inactive mailboxes disappear: Cox says that after 12 months of inactivity “all mailbox contents, folders, contacts, and settings will be permanently deleted” (Cox). An old list with many cox.net contacts therefore has dead addresses, which bounce as a hard bounce.

Run such a list through a bulk email verifier, or check one contact with is this a real email address. The live MX records box on this page shows where cox.net mail is delivered today.

Sources

Checked on October 10, 2026. Server names, ports and sign-in rules come from these official pages:

Other internet providers

Cox email settings: FAQ

What are the cox.net SMTP settings?

Since cox.net email moved to Yahoo: smtp.mail.yahoo.com, port 465 with SSL/TLS or port 587 with STARTTLS, authentication on, user name = your full cox.net address, password = a Yahoo app password.

What are the Cox IMAP settings?

imap.mail.yahoo.com, port 993, SSL/TLS, with your full cox.net address and a Yahoo app password. POP3 is pop.mail.yahoo.com on port 995.

Does Cox still offer email?

No. Cox says it has completed the transition to Yahoo Mail and no longer offers or supports email services. Existing cox.net addresses keep working at Yahoo.

Can I still use my cox.net email address?

Yes. You keep the address and sign in at Yahoo Mail. Cox notes that inactive mailboxes are deleted after 12 months of inactivity.

Email validation API

Validate cox.net addresses before you send

emailvalidation.io checks syntax, MX records and the mailbox over SMTP, flags disposable, role and free addresses and returns a quality score, in one request.

/v1/info Email validation API Read the documentation

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GET https://api.emailvalidation.io/v1/info?email=support@emailvalidation.io

{
  "email": "support@emailvalidation.io",
  "user": "support",
  "tag": "",
  "domain": "emailvalidation.io",
  "format_valid": true,
  "mx_found": true,
  "smtp_check": true,
  "catch_all": null,
  "role": true,
  "disposable": false,
  "free": false,
  "score": 0.64,
  "state": "deliverable",
  "reason": "valid_mailbox",
  "did_you_mean": ""
}

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