Real-time email delivery metrics across major providers
Last updated: Sep 27, 2026 7:25 AM PDT
Current ESP Status
| Provider | P95 Latency (s) | Retry Rate | Trend | Status | Details |
|---|---|---|---|---|---|
| Apple iCloud | 2.67 | 2.3% | ▬ | Healthy | View Details |
| Comcast / Xfinity | 1.04 | 4.4% | ▬ | Healthy | View Details |
| GMX / WEB.de | 1.95 | 0.0% | ▬ | Healthy | View Details |
| Google Mail | 0.80 | 1.3% | ▼ | Healthy | View Details |
| Microsoft 365 | 1.63 | 0.1% | ▬ | Healthy | View Details |
| Outlook / Hotmail | 1.81 | 0.0% | ▬ | Healthy | View Details |
| Spectrum / Charter | 1.30 | 0.0% | ▼ | Healthy | View Details |
| Yahoo / AOL | 1.83 | 0.0% | ▲ | Healthy | View Details |
Details for Apple iCloud
← Back to OverviewP95 Latency (24 hours)
Delivery Issues (24 hours)
Retry and Bounce RatesTop Delivery Failure Reasons (24 hours)
| Reason | Distribution |
|---|---|
| Temporary resource unavailable |
38.9%
|
| Apple CS01 policy rejection |
36.5%
|
| Mailbox over quota |
16.9%
|
| Apple HM08 policy rejection |
4.4%
|
| Unknown |
1.4%
|
| Network error (timeout/refused/reset) |
1.4%
|
| Invalid address (user doesn't exist) |
0.7%
|
About this data
- The numbers on this page come from SMTP telemetry that Groups.io collects each day.
- Latency measures the time from the start of the connection until we receive the server's response to the DATA command.
- Metrics are updated every five minutes and down-sampled into 5-minute buckets; raw data older than seven days is automatically purged, and roll-ups are kept for 90 days.
Need deeper, real-time insight?
- Query ANY domain - not just the majors you see above
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