Real-time email delivery metrics across major providers
Last updated: Aug 23, 2026 8:15 PM PDT
Current ESP Status
| Provider | P95 Latency (s) | Retry Rate | Trend | Status | Details |
|---|---|---|---|---|---|
| Apple iCloud | 2.51 | 3.3% | ▬ | Healthy | View Details |
| Comcast / Xfinity | 1.03 | 9.9% | ▬ | Degraded | View Details |
| GMX / WEB.de | 1.85 | 0.0% | ▬ | Healthy | View Details |
| Google Mail | 0.72 | 2.3% | ▲ | Healthy | View Details |
| Microsoft 365 | 1.43 | 1.8% | ▼ | Healthy | View Details |
| Outlook / Hotmail | 1.52 | 0.0% | ▬ | Healthy | View Details |
| Spectrum / Charter | 1.29 | 11.6% | ▬ | Issues | View Details |
| Yahoo / AOL | 0.72 | 0.0% | ▬ | Healthy | View Details |
Details for Outlook / Hotmail
← Back to OverviewP95 Latency (24 hours)
Delivery Issues (24 hours)
Retry and Bounce RatesTop Delivery Failure Reasons (24 hours)
| Reason | Distribution |
|---|---|
| Invalid address (user doesn't exist) |
85.0%
|
| Temporary resource unavailable |
9.1%
|
| Unknown |
4.0%
|
| Rate limited |
1.5%
|
| DMARC/authentication rejection |
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.
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- Query ANY domain - not just the majors you see above
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