Transactional Email APIs · reliability comparison
Postmark vs Resend: which is more reliable? (2026)
Postmark is more reliable than Resend, scoring 68.3 vs 60.5 out of 100. Over the last 90 days Postmark reported 8 incidents and Resend reported 23, with effective uptime of 99.58% and 99.39% respectively. Resend resolves incidents faster on average (3h 39m).
Data updated Nov 2, 2026 · How we score
| Metric | Postmark | Resend |
|---|---|---|
| Reliability score | 68.3 | 60.5 |
| Rank (transactional email APIs) | #10 | #11 |
| Uptime (90 days) | 99.58% | 99.39% |
| Incidents (90 days) | 8 | 23 |
| Partial / major outages | 0 | 4 |
| Avg time to resolve | 7h 41m | 3h 39m |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where Postmark and Resend differ
- Resend reported 2.9× as many incidents as Postmark over the last 90 days (23 vs 8).
- Resend had 4 partial or major outages, compared with 0 for Postmark.
- Resend fixes problems faster: 3h 39m on average, against 7h 41m for Postmark (2.1× quicker).
- Postmark's longest outage on record lasted 1d 3h (Feb 1, 2026); Resend's lasted 2h 39m (Aug 8, 2026).
90-day uptime
Postmark
Resend
- No incidents
- Degraded
- Partial outage
- Major outage
- No data
Recent Postmark incidents
- Degraded performanceOct 27, 2026 · resolved in 1h 43m
- MaintenanceOct 7, 2026 · resolved in 3h
- Degraded performanceSep 28, 2026 · resolved in 2h 6m
- Degraded performanceSep 28, 2026 · resolved in 3h 59m
- Degraded performanceSep 22, 2026 · resolved in 20m
- Degraded performanceSep 17, 2026 · resolved in 1h 33m
Recent Resend incidents
- Degraded performanceOct 26, 2026 · resolved in 23m
Affected: Email Events
- Degraded performanceOct 23, 2026 · resolved in 49m
Intermittent latency spikes on our emails API
Affected: Broadcast Emails, Batch Emails, Scheduled Emails, Single Email
- Degraded performanceOct 10, 2026 · resolved in 1h 9m
Delayed new team provisioning and contact webhook delivery
Affected: Webhooks, Dashboard, General API
- Degraded performanceOct 9, 2026 · resolved in 23m
Delayed new team provisioning and contact webhook delivery
Affected: Webhooks, Dashboard, General API
- Degraded performanceOct 1, 2026 · resolved in 52m
- Degraded performanceSep 26, 2026 · resolved in 2h 46m
Other transactional email APIs to consider
- Mailjet · #1 · 100% uptime
- Mailtrap Email Sending · #2 · 99.99% uptime
- Loops · #3 · 99.98% uptime
- Twilio SendGrid · #4 · 99.98% uptime
See the full most reliable transactional email apis ranking →