Mailbox provider · 163 Mail (NetEase)
How to verify a 163.com email address
163 Mail (NetEase) addresses can be verified without sending an email. On 12 October 2026 the 163.com mail server 163mx03.mxmail.netease.com rejected a made-up recipient at the SMTP RCPT TO step with 550 User not found, so a mailbox check can tell a missing 163.com account from a real one.
Mailbox checks: Verifiable. The server rejects unknown recipients during the SMTP conversation.
163 Mail (NetEase) at a glance
| Same mailbox system | 126.com uses the same mxmail.netease.com network, with 126mx hostsObserved 12 October 2026 (dig MX) |
|---|---|
| MX hosts | 163mx01, 163mx02, 163mx03.mxmail.netease.com, then 163mx00Observed 12 October 2026 (dig MX) |
| Answer to a made-up address | 550 User not found, returned at RCPT TOObserved 12 October 2026 (SMTP probe of a made-up recipient, no message sent) |
What 163 Mail (NetEase)'s server says about a missing mailbox
The reply that matters is the one to RCPT TO, the step where the checking server names the recipient. 163 Mail (NetEase) answered our made-up 163.com address with 550 User not found. A 5xx code at that step is a permanent "no such mailbox", which is the same answer a real message would get, so SimpleVerifier marks the address invalid with the reason "Mailbox not found". A 250 at the same step means the mailbox exists and comes back valid.
Before trusting a "valid", a careful verifier also offers a random address that cannot exist. 163 Mail (NetEase) rejected ours, so 163.com is not a catch-all: a 250 for your address is a real signal. Temporary 4xx replies (421, 450, 451) are about the connection, not the mailbox, and come back risky with "Server would not confirm" rather than invalid. Hard bounce vs soft bounce explains why that split matters.
Cleaning 163.com addresses on a list
Because 163 Mail (NetEase) answers honestly, 163.com is one of the domains where verification removes bounces before they happen. Drop the invalid results, keep the valid ones, and re-check the risky ones later: a temporary reply on one day often turns into a clear answer the next.
A valid result only means the mailbox exists today. Addresses on an old consumer list go stale as people stop using them, so re-verify before each large send to an aged segment; how often to verify an email list gives a schedule. Upload the CSV to the verifier and download the valid, risky and invalid rows as separate files.
Live DNS check for 163.com
These are 163.com's own sending records, refreshed daily. They describe mail sent from the domain, not whether a given address at it exists.
3 of 5 checks passed
60%Blocklist status
Not listed on SURBL, SpamCop
DKIM — message signing
No DKIM found on common selectors — it may use a custom one
DMARC — spoofing policy
DMARC present but p=none, so nothing is enforced
Mail servers (MX)
4 mail server(s), primary 163mx03.mxmail.netease.com
SPF — authorised senders
SPF present, strict (-all)
Common questions
- Can I check if a 163.com address exists without emailing it?
- Yes. A verifier connects to 163 Mail (NetEase)'s mail server, names the address at the RCPT TO step and disconnects before sending. On 12 October 2026 the server rejected a made-up 163.com address with "550 User not found", so a missing mailbox shows up as invalid and the owner receives nothing.
- What mail servers does 163.com use?
- On 12 October 2026, 163.com published these MX hosts: 163mx01, 163mx02, 163mx03.mxmail.netease.com, then 163mx00. You can look them up yourself with the free MX lookup tool.
- Why did a 163.com address come back risky instead of invalid?
- Risky means the server didn't give a permanent answer during the check, usually a temporary 4xx reply or a timeout. It isn't proof the address is bad. Check it again later; 163 Mail (NetEase) gave a clear rejection for a missing mailbox when we tested it.
Check a 163 Mail (NetEase) address
The free checker runs the mailbox check on one address and shows the server's reason, so you can see which of the cases above applies.