How to Check if an iCloud Email Address Exists (icloud.com, me.com, mac.com)
You can usually check whether an iCloud address exists without sending an email: a mailbox check names the address to Apple's mail server at the RCPT TO step, and in our live checks Apple rejected unknown users with 550 5.1.1 and accepted real ones. icloud.com, me.com and mac.com all run on the same iCloud Mail servers, so they're checked the same way. When Apple gives a temporary reply or refuses the checker, the honest answer is "risky", not "invalid".
Check one now:
Step 1: confirm it's really iCloud Mail
Apple's address domains are icloud.com, me.com and mac.com. On 22 October 2026 all three published the same two MX hosts, mx01.mail.icloud.com and mx02.mail.icloud.com. Apple's postmaster information for iCloud Mail covers the three domains.
A custom domain can also use iCloud Mail (an iCloud+ feature). If a company-looking address has MX records at mail.icloud.com, treat it like an iCloud address. The email provider lookup shows the MX host for any address.
Step 2: run a mailbox check
A mailbox check does what a mail server does at the start of a delivery, then stops:
- Looks up the domain's MX records.
- Connects to Apple's server and offers a random made-up address first, to see whether the domain accepts everything (a catch-all).
- Names your address at
RCPT TO. - Disconnects before any message is sent.
How to read Apple's answer:
| Apple's reply | What it means | Result |
|---|---|---|
| Accepts the address, rejects the random one | The mailbox exists | Valid |
550 5.1.1 for your address |
No such mailbox | Invalid |
| A 4xx temporary reply or deferral | No answer about the mailbox yet | Risky; check again later |
A 5.7.x refusal of the checking server |
Apple refused the checker, not the address | Risky |
Apple doesn't publish how its servers respond to these checks. Everything above comes from our own live checks, and a check that can't get a clear answer should say so instead of guessing. Our post on how to tell if your email verifier is lying shows how to test any tool's answers.
The iCloud email checker does all of this for one address; the bulk iCloud email checker handles a pasted list.
Step 3: handle Hide My Email and relay addresses
iCloud+ subscribers can create Hide My Email addresses. Apple's Hide My Email help describes them as "unique, random email addresses" that forward to the user's real inbox. They look like a random string at icloud.com.
- They're real ways to reach a real person, so don't treat them as fake.
- You can't link one to the person's main address, and a person can deactivate one at any time, after which mail to it stops reaching them.
- A trial user creating many of them is a different problem; see plus addressing and trial abuse.
Step 4: don't confuse a policy bounce with a dead mailbox
If you've already sent and got 554 5.7.1 [CS01] Message rejected due to local policy, that's Apple refusing your message, not saying the address is gone. Our guide to iCloud local policy rejections walks through Apple's sender requirements: SPF, DKIM, a DMARC policy, reverse DNS, a working unsubscribe, and sending only to people who subscribed.
Step 5: check the whole list before you send
Ecommerce, app and consumer lists often have a large share of iCloud addresses, because Apple devices suggest them at signup.
- Fix typo domains first (
icoud.com,iclod.com) with the email typo corrector. - Upload the file on the verify page. Every address gets a live mailbox check, and valid, risky and invalid download as separate files.
- Send to the valid file. Re-check risky iCloud addresses later rather than sending to all of them at once.
If you're cleaning a store's customer list, our post on exporting Shopify customers covers the export side, and the email list cleaning service page explains what a full clean includes.
Where SimpleVerifier fits
The single-address checker is free. For a list, the first 100 checks are free with a Google sign-in, no card. Starter is $9 a month for 2,500 checks; Pro is $39 a month with the first 100,000 checks a month at full speed, then slower, never cut off. See pricing.
Common questions
Can you check if an iCloud email exists without sending an email?
Usually, yes. A mailbox check connects to Apple's mail server, names the address at the RCPT TO step and disconnects before anything is sent. In our live checks Apple rejected unknown users with 550 5.1.1 and accepted existing ones. Apple doesn't publish how it answers these checks, so this rests on our own dated tests.
Are me.com and mac.com addresses still valid?
They can be. me.com and mac.com are older Apple address domains that still run on iCloud Mail and publish the same MX hosts as icloud.com. Check each address; the domain alone doesn't tell you whether the mailbox is open.
Why does an iCloud address come back risky?
Because the check didn't get a clear answer: Apple gave a temporary reply, deferred, or refused the checking server. Risky means unconfirmed, not bad. Check again later, and let the address's source decide whether to send.
What is a Hide My Email address?
An iCloud+ feature Apple describes as unique, random email addresses that forward to the user's real inbox. They reach a real person, but you can't link one to the person's main address.
What does 554 5.7.1 [CS01] mean from iCloud?
It is a policy rejection of your message, not a missing mailbox. Apple doesn't publish what CS01 means, but its postmaster page lists sender requirements such as SPF, DKIM, DMARC and only sending to people who subscribed. Don't suppress the address on this code alone.
Check your list before you send
Real mailbox checks over SMTP, and nothing is sent to the address. Sign in with Google and your first 100 email checks are free, no card. Plans for bigger lists are on the pricing page.