Email domain report
F5 email format (f5.com): verification & catch-all status
As of November 6, 2026, the most common f5.com email format is [email protected], used by 83–100% of the at least 20 distinct f5.com addresses mailfloss verified in the 90 days to November 6, 2026. f5.com routes incoming mail through Cisco Secure Email. In mailfloss's checks (latest November 3, 2026), f5.com mostly accepted mail for addresses that do not exist, so it behaves as a catch-all domain. 74–82% of mailfloss's f5.com verifications in the 90 days to November 6, 2026 were accepted.
One address at a time, right on this page · counts rounded
- Most common format
f.last@- 83–100% of distinct addresses
- Catch-all
- Yes
- mostly accepts any address · checked November 3, 2026
- Accepted on verification
- 74–82%
- of verifications, 90 days to November 6, 2026
Verification results
How f5.com responds to email verification
How f5.com answered when mailfloss verified its addresses in the 90 days to November 6, 2026, most recently on November 3, 2026.
Most common f5.com email formats
| Format | What it means | Share | 95% range | Addresses |
|---|---|---|---|---|
[email protected] | First initial, dot, last name | 83–100% | 62–100% | 20+ |
Shares are of the 20+ distinct f5.com addresses mailfloss verified in the 90 days to November 6, 2026. A range shows where a share can sit given the addresses behind it. Uncommon formats are combined, and the words in each format are placeholders, never real names.
SMTP responses from f5.com
| Response | What it means | Share of listed responses |
|---|---|---|
250 | Mailbox accepted the addressDeliverable | 97–100% |
Only answers about the mailbox itself are listed.
Catch-all
Yes, mostly accepts any address
Last checked November 3, 2026
DNS, checked November 3, 2026
MX mx1.hc5801-97.iphmx.com
SPF published · DMARC published
Mailbox provider Microsoft 365
Free check
Verify an address at f5.com
Type the part before the @. mailfloss asks the f5.com mail server about that address and tells you in seconds what it answered: the same verification behind the results on this page.
Any other domain works too: type a full address. The result appears under the box; nothing you type is stored on this page.
Questions about f5.com
F5 email questions, answered from this data
Every answer comes from the numbers on this page, 90 days to November 6, 2026.
What email domain does F5 use?
f5.com. Its mail is routed through Cisco Secure Email (mx1.hc5801-97.iphmx.com), with SPF published and DMARC published, checked November 3, 2026.
What is the most common f5.com email format?
[email protected]: 83–100% (95% range 62–100%) of the 20+ distinct f5.com addresses mailfloss verified in the 90 days to November 6, 2026.
Is f5.com a catch-all domain?
Yes. In mailfloss's checks (latest November 3, 2026), f5.com mostly accepted mail for addresses that do not exist, so it behaves as a catch-all domain. Verification can confirm that f5.com accepts mail, not that a particular mailbox exists. mailfloss marks these addresses as accept-all instead of valid, so you decide whether to keep sending to them.
Do f5.com addresses bounce?
Of mailfloss's f5.com verifications in the 90 days to November 6, 2026, 74–82% were accepted and 19–24% got no clear answer.
How do I find or check an email address at f5.com?
Build it from the person's name in the most common format, [email protected], then verify it before you send: mailfloss asks the f5.com mail server about that exact address and reports what it answered. Because f5.com accepts mail for any address, verification can confirm that the domain accepts mail, not that the mailbox exists, so mailfloss marks those addresses accept-all. Verify one now.
Does F5 use Google Workspace or Microsoft 365?
Microsoft 365, the mailbox provider on mailfloss's record. Its published MX record points to Cisco Secure Email, a security gateway that filters mail before it reaches the mailbox, going by its public mail records as of November 3, 2026.
Other company domains on Cisco Secure Email
All 4 Cisco Secure Email domains| Domain | Most common format | Accepted on verification | Catch-all |
|---|---|---|---|
| intuit.comIntuit | [email protected]79–98% of addresses | 68–76% | catch-all: No |
| ngc.comNorthrop Grumman | [email protected]88–100% of addresses | 89–96% | catch-all: No |
| rbc.comRBC | [email protected]92–100% of addresses | 77–83% | catch-all: No |
One check is a start. Keep every address on your list deliverable.
mailfloss runs this verification on your whole list, inside your email platform, and keeps running it as addresses change. Product teams and AI agents get the same checks from the API.
Every number here comes from verifications mailfloss ran for its customers in the 90 days to November 6, 2026. Pages show rounded aggregates only: no email addresses, names or single results. Read how mailfloss measures email formats and catch-all status.
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