UC Worker shared mailbox provider

According to Live Direct Marketing's daily Tranco top-1M scan (July 13, 2026), UC Worker shared is the mailbox provider for 36 domains — 0.01% of 658,711 domains with MX records. Detection method: primary MX record (lowest preference).

Key facts

UC Worker shared is a mailbox provider operating as a primary MX record handler for websites in the Tranco top-one-million list. It serves a distributed footprint of smaller and medium-sized sites rather than global incumbents, with particularly high concentration in the .th (Thailand) domain namespace.

For email practitioners, UC Worker shared's presence signals a regional, long-tail provider in the infrastructure landscape. Its relevance to your deliverability programme depends on your sender footprint: if your email reaches Thai domains or regional Southeast Asian infrastructure, it warrants monitoring and testing; for globally focused sending, it typically ranks below major incumbent providers in testing priority.

Where UC Worker shared sits in the Tranco ranking

Tranco rank bandDomainsShare of its base
Top 1,00000.0%
Top 10,00012.8%
Top 100,00038.3%
Top 1,000,0002877.8%
Unranked411.1%

Top-level domain split

TLDDomainsShare
.th3597.2%
.co.th12.8%

Significance for regional and long-tail testing

UC Worker shared's concentration in the .th space and positioning among smaller sites means its inclusion in deliverability audits is contextual. If your sender reputation and monitoring programmes span Thai domains or decentralised regional infrastructure, UC Worker shared merits attention; if your audience is primarily global or outside Thailand, it generally falls below the threshold for dedicated monitoring, though long-tail providers occasionally surface filtering or reputation anomalies worth capturing in broader audits.

See the full UC Worker shared data page (KPI cards, trend, sample domains) →

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Frequently asked questions

What is UC Worker shared and when should I test against it?

UC Worker shared is a mailbox provider handling email for smaller websites, concentrated in the .th domain space. Include it in your testing and reputation monitoring if you send to or audit Thai regional infrastructure; otherwise, prioritise larger incumbent providers unless your broader auditing strategy captures long-tail variance.

How many domains use UC Worker shared?

36 domains in the Tranco top-1M use UC Worker shared as their mailbox provider as of July 13, 2026 (0.01% of domains with MX records), according to Live Direct Marketing's daily DNS scan.

Is UC Worker shared common enough to affect email deliverability testing?

UC Worker shared accounts for 0.01% 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 UC Worker shared most?

UC Worker shared's largest TLD is .th (97.2% of its domains); it appears across 2 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%)