Transactional Email APIs · reliability comparison
MailerSend vs Resend: which is more reliable? (2026)
MailerSend is more reliable than Resend, scoring 100.0 vs 60.5 out of 100. Over the last 90 days MailerSend reported 0 incidents and Resend reported 23, with effective uptime of 100% and 99.39% respectively.
Data updated Nov 2, 2026 · How we score
| Metric | MailerSend | Resend |
|---|---|---|
| Reliability score | 100.0 | 60.5 |
| Rank (transactional email APIs) | — | #11 |
| Uptime (90 days) | 100% | 99.39% |
| Incidents (90 days) | 0 | 23 |
| Partial / major outages | 0 | 4 |
| Avg time to resolve | — | 3h 39m |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where MailerSend and Resend differ
- MailerSend reported no incidents in the last 90 days, while Resend reported 23.
- Resend had 4 partial or major outages, compared with 0 for MailerSend.
90-day uptime
MailerSend
Resend
- No incidents
- Degraded
- Partial outage
- Major outage
- No data
Recent MailerSend incidents
- MaintenanceSep 23, 2026 · ongoing
Affected: SMTP, Email activity, Delivery time, Email sending API, Email analytics, Deliverability rate +2 more
- MaintenanceSep 15, 2026 · ongoing
Scheduled maintenance - Email sending affected, 5 min
Affected: Bulk endpoint, SMTP, Delivery time, Email sending API, Inbound routing
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: Single Email, Broadcast Emails, Batch Emails, Scheduled Emails
- Degraded performanceOct 10, 2026 · resolved in 1h 9m
Delayed new team provisioning and contact webhook delivery
Affected: General API, Webhooks, Dashboard
- Degraded performanceOct 9, 2026 · resolved in 23m
Delayed new team provisioning and contact webhook delivery
Affected: Dashboard, General API, Webhooks
- 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 →