According to Live Direct Marketing's daily Tranco top-1M scan (July 12, 2026), Mailtrap is the email service provider (ESP) for 518 domains — 0.08% of 617,244 SPF-publishing domains. Detection method: include: mechanisms in the SPF record.
Mailtrap is a transactional email platform developed by Railsware that provides hosted SMTP infrastructure for application-generated mail. It serves organisations that need reliable outbound email delivery without operating their own mail servers, offering both a sandbox testing environment for development and production relay services.
Mailtrap's footprint across SPF records shows it occupies the infrastructure layer for smaller and mid-market organisations rather than enterprise-scale deployments. Its frequent co-occurrence with Google Workspace indicates a common pattern where organisations use Google for primary email but route application notifications through Mailtrap's managed infrastructure, and its global distribution reflects adoption across diverse geographies and business verticals.
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 4 | 0.8% |
| Top 100,000 | 54 | 10.4% |
| Top 1,000,000 | 398 | 76.8% |
| Unranked | 62 | 12.0% |
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 228 | 44.0% | |
| .com.br | 21 | 4.1% | |
| .io | 19 | 3.7% | |
| .org | 19 | 3.7% | |
| .net | 18 | 3.5% | |
| .nl | 10 | 1.9% | |
| .fr | 9 | 1.7% | |
| .it | 9 | 1.7% | |
| .ch | 9 | 1.7% | |
| .id | 7 | 1.4% |
Cross-tabulated from the same daily snapshot — the other email services seen on the same 518 domains.
| Type | Service | Domains | Share of Mailtrap users |
|---|---|---|---|
| Mailbox | Google Workspace | 183 | 35.3% |
| Mailbox | Microsoft 365 | 98 | 18.9% |
| Mailbox | Self-Hosted | 49 | 9.5% |
| Mailbox | Unknown / Other | 29 | 5.6% |
| Mailbox | Zoho Mail | 22 | 4.2% |
| Mailbox | Cloudflare Email Routing | 10 | 1.9% |
| ESP | Amazon SES | 59 | 11.4% |
| ESP | Zendesk | 36 | 6.9% |
| ESP | MailerSend | 32 | 6.2% |
| ESP | Mailgun | 31 | 6.0% |
Organisations using Mailtrap as a mail relay must include Mailtrap's SMTP infrastructure in their domain's SPF record to pass authentication checks. Because Mailtrap operates shared IP addresses used by many customers simultaneously, sender reputation is influenced by the collective sending behaviour of all users on that IP block; poor list hygiene or spam complaints from other customers can result in shared-IP blacklisting that affects all senders using that IP.
See the full Mailtrap data page (KPI cards, trend, sample domains) →
Mailtrap can validate SMTP delivery and message formatting, but as a mail relay it does not simulate delivery to consumer mailboxes like Gmail or Outlook. For production deliverability testing, integrate with real mailbox providers or dedicated testing services.
518 domains in the Tranco top-1M use Mailtrap as their email service provider (ESP) as of July 12, 2026 (0.08% of SPF-publishing domains), according to Live Direct Marketing's daily DNS scan.
Mailtrap accounts for 0.08% 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.
Mailtrap's largest TLD is .com (44.0% of its domains); it appears across 97 TLDs in total.