Mailbox.org mailbox provider

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), Mailbox.org is the mailbox provider for 358 domains — 0.05% of 658,711 domains with MX records. Detection method: primary MX record (lowest preference).

Key facts

Mailbox.org is a privacy-focused email provider operated by Mailbox.org GmbH, a German company. It serves individual users and small organisations across Europe, positioning itself around data protection and user autonomy rather than enterprise-scale delivery.

In the Tranco top-1M footprint, Mailbox.org appears predominantly in the long tail of smaller web properties rather than among the world's largest brands, with pronounced concentration in German-speaking markets. For senders, this means Mailbox.org addresses are less common in mainstream bulk-mail lists but concentrated in European and privacy-conscious segments; for deliverability professionals, understanding Mailbox.org's authentication and filtering practices matters mainly when serving regional or European-focused audiences.

Where Mailbox.org sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00000.0%
Top 10,00051.4%
Top 100,0004512.6%
Top 1,000,00024769.0%
Unranked6117.0%

Top-level domain split

TLDDomainsShare
.de10830.2%
.com8523.7%
.net359.8%
.org328.9%
.eu113.1%
.io72.0%
.app72.0%
.dev72.0%
.com.br41.1%
.info41.1%

What Mailbox.org users also use

Cross-tabulated from the same daily snapshot — the other email services seen on the same 358 domains.

TypeServiceDomainsShare of Mailbox.org users
ESPAmazon SES215.9%
ESPConstant Contact154.2%
ESPZendesk123.4%
ESPBrevo (ex-Sendinblue)123.4%
ESPMailjet (Sinch)113.1%
ESPNewsletter2Go (Brevo)61.7%
ESPMailchimp41.1%
ESPPostmark30.8%
ESPScaleway TEM20.6%
ESPMailerSend20.6%

Regional footprint and sender reputation monitoring

Because Mailbox.org sits primarily in smaller web properties and German-language markets rather than among the largest global websites, sender reputation at Mailbox.org should be monitored as a distinct regional signal rather than rolled into global metrics. Organisations serving European or German-speaking audiences can expect regular exposure to Mailbox.org subscribers and should include the provider in their regional deliverability assessments; those focused on global bulk delivery can deprioritise it without material impact on reach.

See the full Mailbox.org data page (KPI cards, trend, sample domains) →

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Frequently asked questions

Should I test my email delivery against Mailbox.org?

If your audience spans Europe or German-speaking regions, Mailbox.org is worth including in your regional test matrix; otherwise, its presence in the long tail of smaller websites means it can be deprioritised in global deliverability testing.

How many domains use Mailbox.org?

358 domains in the Tranco top-1M use Mailbox.org as their mailbox provider as of July 13, 2026 (0.05% of domains with MX records), according to Live Direct Marketing's daily DNS scan.

Is Mailbox.org common enough to affect email deliverability testing?

Mailbox.org accounts for 0.05% 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 Mailbox.org most?

Mailbox.org's largest TLD is .de (30.2% of its domains); it appears across 49 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%)