CSC / NetNames mailbox provider
According to Live Direct Marketing's daily Tranco top-1M scan (September 24, 2026), CSC / NetNames is the mailbox provider for 111 domains — 0.02% of 675,489 domains with MX records. Detection method: primary MX record (lowest preference).
Key facts
- 111 domains in the Tranco top-1M use CSC / NetNames (0.02% of domains with MX records).
- Snapshot date: 2026-09-24 — recomputed every day.
- Strongest TLD: .com (43.2% of its domains).
- Region skew: Global / US-skewed.
- Most co-used service: Campaign Monitor.
- Directory category: corporate mail infrastructure.
Why CSC / NetNames appears in this category
Legacy NetNames corporate email relay infrastructure, now part of CSC.
We classify it as a corporate mail infrastructure 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.
What the data shows
92.8% of its domains sit outside the top 100,000 — a long-tail footprint spread across smaller sites. It spans 36 TLDs, led by .com (43.2%) — a broad, internationally distributed base. The service most often seen alongside it is Campaign Monitor (ESP), on 3.6% of its domains.
Where CSC / NetNames sits in the Tranco ranking
| Tranco rank band | Domains | Share of its base |
|---|---|---|
| Top 1,000 | 0 | 0.0% |
| Top 10,000 | 0 | 0.0% |
| Top 100,000 | 7 | 6.3% |
| Top 1,000,000 | 103 | 92.8% |
| Unranked | 1 | 0.9% |
Top-level domain split
| TLD | Domains | Share | |
|---|---|---|---|
| .com | 48 | 43.2% | |
| .co.uk | 13 | 11.7% | |
| .net | 5 | 4.5% | |
| .org | 4 | 3.6% | |
| .org.uk | 3 | 2.7% | |
| .de | 3 | 2.7% | |
| .fr | 3 | 2.7% | |
| .es | 2 | 1.8% | |
| .io | 2 | 1.8% | |
| .ch | 2 | 1.8% |
What CSC / NetNames users also use
Cross-tabulated from the same daily snapshot — the other email services seen on the same 111 domains.
| Type | Service | Domains | Share of CSC / NetNames users |
|---|---|---|---|
| ESP | Campaign Monitor | 4 | 3.6% |
| ESP | Proofpoint | 3 | 2.7% |
| ESP | Sophos Email | 2 | 1.8% |
| ESP | SMTP2GO | 1 | 0.9% |
| ESP | SALESmanago (PL) | 1 | 0.9% |
| ESP | SendGrid (Twilio) | 1 | 0.9% |
| ESP | Adestra (MessageFocus) | 1 | 0.9% |
| ESP | Mimecast | 1 | 0.9% |
| ESP | Salesforce | 1 | 0.9% |
See the full CSC / NetNames data page (KPI cards, trend, sample domains) →
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Frequently asked questions
How many domains use CSC / NetNames?
111 domains in the Tranco top-1M use CSC / NetNames as their mailbox provider as of September 24, 2026 (0.02% of domains with MX records), according to Live Direct Marketing's daily DNS scan.
Is CSC / NetNames common enough to affect email deliverability testing?
CSC / NetNames 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 CSC / NetNames most?
CSC / NetNames's largest TLD is .com (43.2% of its domains); it appears across 36 TLDs in total.