StackMail (UK mailbox) mailbox provider
According to Live Direct Marketing's daily Tranco top-1M scan (September 24, 2026), StackMail (UK mailbox) is the mailbox provider for 1,196 domains — 0.18% of 675,489 domains with MX records. Detection method: primary MX record (lowest preference).
Key facts
- 1,196 domains in the Tranco top-1M use StackMail (UK mailbox) (0.18% of domains with MX records).
- Snapshot date: 2026-09-24 — recomputed every day.
- Strongest TLD: .com (45.0% of its domains).
- Region skew: Global / US-skewed.
- Most co-used service: StackMail.
- Directory category: mailbox provider.
Why StackMail (UK mailbox) appears in this category
UK shared webmail / IMAP service used by registrars and resellers.
We classify it as a mailbox provider from primary MX record (lowest preference) matching a maintained provider rule. This is infrastructure attribution from public DNS, not evidence of a direct contract or exclusive use.
StackMail (UK mailbox) is a mailbox hosting provider that supplies email infrastructure to small and mid-market websites. It operates as a managed email service, handling inbound and outbound mail for sites that choose not to run their own mail stack.
StackMail's presence across the Tranco top-1M list is concentrated in smaller domains and the .com namespace, with a global but US-skewed distribution. This pattern means senders and operators encounter StackMail most often in long-tail sites rather than the largest brands, making it a relevant secondary consideration for email programmes targeting broad or SMB-focused audiences.
Where StackMail (UK mailbox) sits in the Tranco ranking
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 1 | 0.1% |
| Top 100,000 | 41 | 3.4% |
| Top 1,000,000 | 1,134 | 94.8% |
| Unranked | 20 | 1.7% |
Top-level domain split
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 538 | 45.0% | |
| .co.uk | 303 | 25.3% | |
| .net | 59 | 4.9% | |
| .uk | 42 | 3.5% | |
| .org | 32 | 2.7% | |
| .org.uk | 28 | 2.3% | |
| .pk | 12 | 1.0% | |
| .site | 11 | 0.9% | |
| .ma | 11 | 0.9% | |
| .in | 10 | 0.8% |
What StackMail (UK mailbox) users also use
Cross-tabulated from the same daily snapshot — the other email services seen on the same 1,196 domains.
| Type | Service | Domains | Share of StackMail (UK mailbox) users |
|---|---|---|---|
| ESP | StackMail | 1,026 | 85.8% |
| ESP | MailerLite | 14 | 1.2% |
| ESP | Amazon SES | 10 | 0.8% |
| ESP | Mailchimp | 8 | 0.7% |
| ESP | Mandrill | 5 | 0.4% |
| ESP | SendGrid (Twilio) | 4 | 0.3% |
| ESP | SenderSRV | 4 | 0.3% |
| ESP | Elastic Email | 4 | 0.3% |
| ESP | Mailjet (Sinch) | 4 | 0.3% |
| ESP | Brevo (ex-Sendinblue) | 3 | 0.3% |
StackMail in the email ecosystem
StackMail occupies a niche as a mailbox provider for smaller sites and SMBs, which means bounce handling, authentication strictness, and filtering posture can vary across StackMail-hosted domains depending on individual site configuration. This variation makes StackMail an important checkpoint for senders targeting broad, long-tail, or SMB audiences rather than enterprise domains only.
See the full StackMail (UK mailbox) data page (KPI cards, trend, sample domains) →
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Frequently asked questions
What is StackMail, and should I test email deliverability against it?
StackMail is a mailbox hosting provider used primarily by smaller sites and SMBs across .com domains. Testing against StackMail is relevant if your recipient list includes long-tail or SMB addresses; otherwise, it is a secondary consideration.
How many domains use StackMail (UK mailbox)?
1,196 domains in the Tranco top-1M use StackMail (UK mailbox) as their mailbox provider as of September 24, 2026 (0.18% of domains with MX records), according to Live Direct Marketing's daily DNS scan.
Is StackMail (UK mailbox) common enough to affect email deliverability testing?
StackMail (UK mailbox) accounts for 0.18% 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 StackMail (UK mailbox) most?
StackMail (UK mailbox)'s largest TLD is .com (45.0% of its domains); it appears across 85 TLDs in total.