Real-time email delivery metrics across major providers
Last updated: Aug 2, 2026 10:15 PM PDT
Current ESP Status
| Provider | P95 Latency (s) | Retry Rate | Trend | Status | Details |
|---|---|---|---|---|---|
| Apple iCloud | 3.72 | 0.4% | ▲ | Degraded | View Details |
| Comcast / Xfinity | 1.05 | 3.5% | ▲ | Healthy | View Details |
| GMX / WEB.de | 1.95 | 0.0% | ▬ | Healthy | View Details |
| Google Mail | 0.61 | 1.5% | ▬ | Healthy | View Details |
| Microsoft 365 | 1.89 | 0.8% | ▲ | Healthy | View Details |
| Outlook / Hotmail | 1.48 | 0.0% | ▬ | Healthy | View Details |
| Spectrum / Charter | 1.08 | 0.0% | ▲ | Healthy | View Details |
| Yahoo / AOL | 1.46 | 7.8% | ▬ | Degraded | 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 |
|---|---|
| Mailbox over quota |
37.6%
|
| Apple CS01 policy rejection |
36.4%
|
| Temporary resource unavailable |
12.4%
|
| Apple HM08 policy rejection |
12.0%
|
| Unknown |
1.2%
|
| Message too large |
0.4%
|
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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