Real-time email delivery metrics across major providers
Last updated: Sep 21, 2026 10:05 AM PDT
Current ESP Status
| Provider | P95 Latency (s) | Retry Rate | Trend | Status | Details |
|---|---|---|---|---|---|
| Apple iCloud | 3.21 | 0.2% | ▲ | Degraded | View Details |
| Comcast / Xfinity | 0.99 | 0.7% | ▬ | Healthy | View Details |
| GMX / WEB.de | 1.89 | 0.0% | ▬ | Healthy | View Details |
| Google Mail | 0.94 | 0.5% | ▲ | Healthy | View Details |
| Microsoft 365 | 1.45 | 0.4% | ▼ | Healthy | View Details |
| Outlook / Hotmail | 1.82 | 0.0% | ▲ | Healthy | View Details |
| Spectrum / Charter | 3.32 | 0.0% | ▲ | Degraded | View Details |
| Yahoo / AOL | 1.26 | 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 |
|---|---|
| Apple HM08 policy rejection |
35.4%
|
| Mailbox over quota |
21.8%
|
| Temporary resource unavailable |
21.8%
|
| Apple CS01 policy rejection |
16.3%
|
| Network error (timeout/refused/reset) |
2.0%
|
| Message too large |
1.4%
|
| Unknown |
0.7%
|
| 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.
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