Hosted Email (Rackspace/IONOS) mailbox provider

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), Hosted Email (Rackspace/IONOS) is the mailbox provider for 1,752 domains — 0.27% of 658,711 domains with MX records. Detection method: primary MX record (lowest preference).

Key facts

Hosted Email is IONOS's mailbox hosting service, providing domain-linked email accounts for businesses and individuals. The service is operated by IONOS (formerly 1&1), a major domain registrar and hosting provider.

Across the web, Hosted Email's presence clusters in the long tail of smaller and mid-market websites, predominantly in the .com domain space, with particular prevalence in the United States. It frequently appears alongside domain forwarding services, reflecting a user base of smaller operations with varied email infrastructure maturity—a pattern that matters for anyone testing deliverability or diagnosing mail flow issues involving Hosted Email domains.

Where Hosted Email (Rackspace/IONOS) sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00010.1%
Top 10,00080.5%
Top 100,000693.9%
Top 1,000,0001,14465.3%
Unranked53030.3%

Top-level domain split

TLDDomainsShare
.com1,16566.5%
.net1206.8%
.org704.0%
.shop372.1%
.ca321.8%
.store311.8%
.co.uk241.4%
.fr201.1%
.in191.1%
.io150.9%

What Hosted Email (Rackspace/IONOS) users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 1,752 domains.

TypeServiceDomainsShare of Hosted Email (Rackspace/IONOS) users
ESPWild West Domains Forwarder925.3%
ESPAmazon SES573.3%
ESPMailgun432.5%
ESPSendGrid (Twilio)251.4%
ESPMailerSend201.1%
ESPZendesk191.1%
ESPMailchimp191.1%
ESPMandrill171.0%
ESPSalesforce80.5%
ESPHubSpot80.5%

Hosted Email and domain forwarding

Hosted Email is commonly deployed alongside Wild West Domains Forwarder and similar domain forwarding services, a pairing that reflects smaller sites' preference for integrated domain and mailbox solutions. This co-occurrence matters for deliverability because forwarding chains can complicate SPF alignment and DKIM signature preservation—mail routed through forwarders may fail authentication checks if the forwarding service does not properly preserve cryptographic headers. Senders targeting Hosted Email recipients should verify that forwarding paths maintain DKIM integrity and that SPF records account for any intermediate mail handlers.

See the full Hosted Email (Rackspace/IONOS) data page (KPI cards, trend, sample domains) →

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Frequently asked questions

What is Hosted Email and should I test deliverability against it?

Hosted Email is IONOS's mailbox hosting product, commonly used by smaller websites and domain owners who want mail tied to their own domain. Testing against it is useful if your recipient base includes these smaller sites, though the more critical factor is whether your customer segment typically uses Hosted Email or competing providers.

How many domains use Hosted Email (Rackspace/IONOS)?

1,752 domains in the Tranco top-1M use Hosted Email (Rackspace/IONOS) as their mailbox provider as of July 13, 2026 (0.27% of domains with MX records), according to Live Direct Marketing's daily DNS scan.

Is Hosted Email (Rackspace/IONOS) common enough to affect email deliverability testing?

Hosted Email (Rackspace/IONOS) accounts for 0.27% of domains with MX records 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 Hosted Email (Rackspace/IONOS) most?

Hosted Email (Rackspace/IONOS)'s largest TLD is .com (66.5% of its domains); it appears across 91 TLDs in total.

Other mailbox providers

Self-Hosted (22.44%)Google Workspace (21.79%)Microsoft 365 (16.74%)Unknown / Other (7.54%)Generic / unmatched (mx*.*) (2.57%)Proofpoint (1.90%)Generic / unmatched (mail.*) (1.75%)Yandex 360 (1.64%)Cloudflare Email Routing (1.60%)Mimecast (1.52%)