Hostopia / CarrierZone mailbox provider

According to Live Direct Marketing's daily Tranco top-1M scan (July 12, 2026), Hostopia / CarrierZone is the mailbox provider for 137 domains — 0.02% of 658,108 domains with MX records. Detection method: primary MX record (lowest preference).

Key facts

Hostopia and CarrierZone provide bundled domain registration, web hosting, and email services for smaller websites globally, with concentrated presence in the .com namespace. These are not enterprise mail platforms; customers typically use them for all-in-one simplicity rather than bespoke infrastructure.

Hostopia occupies the long tail of the web—smaller brands rather than global platforms—making it a lower priority for email testing than major ISPs. However, its frequent pairing with Customer.io indicates significant volumes of transactional and marketing email flow through Hostopia's infrastructure, meaning inbox filtering and sender reputation remain relevant to delivery success even at smaller scale.

Where Hostopia / CarrierZone sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00000.0%
Top 10,00032.2%
Top 100,000139.5%
Top 1,000,00010274.5%
Unranked1913.9%

Top-level domain split

TLDDomainsShare
.com6648.2%
.net3928.5%
.org107.3%
.com.mx96.6%
.mx64.4%
.co.uk21.5%
.ca10.7%
.co10.7%
.com.br10.7%
.biz10.7%

What Hostopia / CarrierZone users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 137 domains.

TypeServiceDomainsShare of Hostopia / CarrierZone users
ESPCustomer.io21.5%
ESPConstant Contact10.7%
ESPMailerSend10.7%
ESPMandrill10.7%
ESPMailChannels10.7%
ESPMailchimp10.7%
ESPHubSpot10.7%
ESPKMITD (TH)10.7%
ESPAmazon SES10.7%
ESPElastic Email10.7%

Shared IP pools and cross-customer reputation risk

Many customers on Hostopia and CarrierZone share IP addresses for outbound mail, a common architecture for shared hosting providers. This means your deliverability can be affected by other senders' reputation on the same IP; if another customer engages in poor sending practices, it may reduce your delivery rates. Monitoring your sending IP reputation externally is advisable if you rely on Hostopia for outbound mail, and requesting a dedicated IP—if available—can isolate your sender reputation.

See the full Hostopia / CarrierZone data page (KPI cards, trend, sample domains) →

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Frequently asked questions

Should I test my email against Hostopia as a priority?

Hostopia is a long-tail provider serving smaller websites, so testing against it is lower priority than major ISPs. However, if your recipient base includes small businesses or startups—especially those using transactional email platforms—include Hostopia in your test matrix.

How many domains use Hostopia / CarrierZone?

137 domains in the Tranco top-1M use Hostopia / CarrierZone as their mailbox provider as of July 12, 2026 (0.02% of domains with MX records), according to Live Direct Marketing's daily DNS scan.

Is Hostopia / CarrierZone common enough to affect email deliverability testing?

Hostopia / CarrierZone accounts for 0.02% 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 Hostopia / CarrierZone most?

Hostopia / CarrierZone's largest TLD is .com (48.2% of its domains); it appears across 11 TLDs in total.

Other mailbox providers

Self-Hosted (22.43%)Google Workspace (21.78%)Microsoft 365 (16.73%)Unknown / Other (7.76%)Generic / unmatched (mx*.*) (2.77%)Proofpoint (1.90%)Generic / unmatched (mail.*) (1.75%)Yandex 360 (1.64%)Cloudflare Email Routing (1.59%)Mimecast (1.52%)