Paubox email provider statistics and deliverability context
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According to Live Direct Marketing's daily Tranco top-1M scan (September 24, 2026), Paubox is the email service provider (ESP) for 172 domains — 0.03% of 637,420 SPF-publishing domains. Its strongest TLD is .com (78.5% of its domains). Detection: include: mechanisms in the SPF record.
Last updated from the 2026-09-24 DNS snapshot.
What Paubox represents in this dataset
Paubox — HIPAA-compliant email gateway.
Directory category: Gateway. The classification comes from include: mechanisms in the SPF record. It describes observed DNS infrastructure, not a commercial relationship and not the placement of any individual message.
What the 2026-09-24 snapshot shows about Paubox
Across 12 distinct TLDs its top three are .com (78.5%), .org (9.9%), .net (3.5%) — together 91.9% of the 172 domains, which makes the footprint narrow — three TLDs cover most of it, which is typical of a regional or single-market operator. The service most often observed on the same domains is Google Workspace (Mailbox, 74 domains, 43.0% of them), followed by Microsoft 365 (25.0%). Directly comparable by the same detection rule: Amazon SES, SendGrid (Twilio), Mailgun. Ranking between them reflects what is published in DNS, not delivery quality or volume sent. All figures come from a single daily DNS snapshot (2026-09-24); a domain appears here when its published records match the include: mechanisms in the SPF record rule, which is an infrastructure fact, not a commercial relationship.
Commonly used together with Paubox
What else the same 172 domains use — cross-tabulated from the same daily snapshot (2026-09-24).
| Type | Service | Domains | Share of Paubox users |
|---|---|---|---|
| Mailbox | Google Workspace | 74 | 43.0% |
| Mailbox | Microsoft 365 | 43 | 25.0% |
| Mailbox | Proofpoint | 12 | 7.0% |
| Mailbox | Generic / unmatched (mx*.*) | 12 | 7.0% |
| Mailbox | Mimecast | 8 | 4.7% |
| Mailbox | Unknown / Other | 6 | 3.5% |
| ESP | HubSpot | 45 | 26.2% |
| ESP | Salesforce | 40 | 23.3% |
| ESP | Zendesk | 29 | 16.9% |
| ESP | Amazon SES | 23 | 13.4% |
TLD distribution (top 12 of 12)
Frequently asked questions
How many domains use Paubox?
172 domains in the Tranco top-1M use Paubox as their email service provider (ESP) as of September 24, 2026, according to Live Direct Marketing's daily DNS scan.
What is Paubox's market share?
Paubox holds 0.03% of SPF-publishing domains in the Tranco top-1M (snapshot of 2026-09-24). The number is recomputed every day.
What are the biggest alternatives to Paubox?
The largest email service provider (ESP)s in the same category by Tranco top-1M share are: Amazon SES, SendGrid (Twilio), Mailgun, Zendesk, Mailchimp (as of 2026-09-24).
Largest email service provider (ESP)s in this category
Amazon SES (6.23%) · SendGrid (Twilio) (4.68%) · Mailgun (4.01%) · Zendesk (3.77%) · Mailchimp (3.61%) · Mandrill (3.26%) · HubSpot (3.18%) · Salesforce (2.57%) · Mailjet (Sinch) (2.14%) · Cloudflare Email Routing (1.96%)
Domain sample (top 100 by Tranco rank)
Showing 100 of 172 domains.