Port 995 – POP3S

TCP

Port 995 is POP3S – POP3 with implicit TLS. The TLS handshake completes before any POP3 commands are exchanged. This is the secure version of POP3 port 110. While POP3 is largely superseded by IMAP for multi-device access, POP3S on port 995 remains in use for legacy clients and simple single-device setups.

Port Number

995

Protocol

TCP

Service

POP3 over TLS

Range

IANA Well-Known (0–1023)

Description

POP3S on port 995 provides the same email download semantics as port 110 but over an encrypted TLS channel established immediately on connection. For users who prefer POP3's download-and-delete model (e.g., local email archiving), POP3S is the correct choice over plaintext POP3.

Security risks

1Single-device model risk: POP3 downloads and deletes mail from the server. If an attacker gets credentials, they connect on 995 first and download all mail – the legitimate user never sees it and there is no server-side evidence.
2Legacy client vulnerabilities: POP3S is used by older email clients that may not validate certificates properly or support modern TLS versions. Ensure your server enforces TLS 1.2+ and disables SSLv3/TLS 1.0.

Firewall guidance

Allow inbound 995 if you must support POP3 clients. Prefer migrating users to IMAP on port 993 for multi-device support. POP3S is acceptable for automated mail processing scripts that download and archive messages locally.

Diagnosis commands

Test POP3S TLS connection – should see certificate immediately

shell

openssl s_client -connect host:995

Audit TLS configuration on POP3S

shell

nmap -p 995 --script ssl-enum-ciphers target

Usage examples

Port 995 – POP3S

shell

openssl s_client -connect mail.example.com:995
USER [email protected]
PASS secret
RETR 1

Common services on this port

DovecotCourierhMailServerMicrosoft ExchangeCyrusGmail POP3

Related ports

110

POP3 (plaintext)

993

IMAPS (preferred alternative)

143

IMAP (STARTTLS)

History

POP3S on port 995 was formalized alongside IMAPS (993) in the late 1990s. RFC 2595 (1999) documented TLS usage with POP3. As IMAP became dominant for multi-device email, POP3S usage declined but persists for simple archival use cases.

FAQ

Is POP3S still relevant in 2026?

Marginally. IMAP (993) is preferred for all interactive email use. POP3S remains useful for: automated mail processing scripts, single-device offline archiving, and legacy systems that cannot be upgraded to IMAP. Gmail still offers POP3 access on port 995.

Specification

RFC 2595 – Port 995 specification →