Exclaimer email service provider (ESP)

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), Exclaimer is the email service provider (ESP) for 739 domains — 0.12% of 617,702 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.

Key facts

Exclaimer is an email signature and compliance management provider that inserts itself into organisations' email infrastructure, typically via SPF includes and message processing. The service handles outbound email branding, disclaimers, compliance controls, and related governance on behalf of its customers.

Exclaimer's detected footprint sits predominantly in the long tail of smaller and mid-market organisations rather than the largest enterprises, with particular prevalence alongside Microsoft 365 deployments. This distribution suggests the service appeals to firms seeking centralised signature and compliance management without the internal resources or scale-driven economics to build such systems themselves.

Where Exclaimer sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00000.0%
Top 10,00000.0%
Top 100,000598.0%
Top 1,000,00058979.7%
Unranked9112.3%

Top-level domain split

TLDDomainsShare
.com27437.1%
.co.uk18324.8%
.com.au8611.6%
.org608.1%
.org.uk385.1%
.au324.3%
.co.nz81.1%
.net70.9%
.ac.uk60.8%
.co40.5%

What Exclaimer users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 739 domains.

TypeServiceDomainsShare of Exclaimer users
MailboxMicrosoft 36548966.2%
MailboxMimecast9613.0%
MailboxUnknown / Other415.5%
MailboxBarracuda314.2%
MailboxProofpoint Essentials152.0%
MailboxProofpoint141.9%
ESPMailchimp13618.4%
ESPSendGrid (Twilio)11916.1%
ESPAmazon SES10814.6%
ESPMandrill10514.2%

SPF authentication chain and sporadic infrastructure encounters

Exclaimer's inclusion in SPF records adds an authorisation checkpoint to the sender authentication chain, but because it is thinly distributed across many smaller organisations rather than concentrated in a handful of major brands, email receivers encounter it irregularly in their inbound streams. This sparse visibility means Exclaimer's infrastructure is unlikely to receive the same reputation optimisation and monitoring attention from large-scale email providers as more densely deployed services do, requiring both senders and receivers to understand its role when diagnosing authentication or deliverability problems involving organisations that use it.

See the full Exclaimer data page (KPI cards, trend, sample domains) →

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Frequently asked questions

Why does an organisation's SPF record include Exclaimer?

Exclaimer processes or relays outbound email on behalf of organisations to apply signatures, disclaimers, and compliance policies; it must be included in their SPF authorisation list so receiving mail servers recognise its traffic as legitimate.

How many domains use Exclaimer?

739 domains in the Tranco top-1M use Exclaimer as their email service provider (ESP) as of July 13, 2026 (0.12% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.

Is Exclaimer common enough to affect email deliverability testing?

Exclaimer accounts for 0.12% of SPF-publishing domains in the top 1M. Whether you should seed a test mailbox there depends on how much of your audience it represents — the co-usage table above shows the services it appears alongside most.

Which countries or TLDs use Exclaimer most?

Exclaimer's largest TLD is .com (37.1% of its domains); it appears across 36 TLDs in total.

Other email service provider (ESP)s

Amazon SES (6.21%)SendGrid (Twilio) (4.76%)Mailgun (4.11%)Zendesk (3.86%)Mailchimp (3.69%)Mandrill (3.36%)HubSpot (3.18%)Salesforce (2.62%)Mailjet (Sinch) (2.13%)Cloudflare Email Routing (1.80%)