Transactional Email APIs · reliability comparison
MailerSend vs SMTP2GO: which is more reliable? (2026)
MailerSend is more reliable than SMTP2GO, scoring 100.0 vs 58.4 out of 100. Over the last 90 days MailerSend reported 0 incidents and SMTP2GO reported 17, with effective uptime of 100% and 99.17% respectively.
Data updated Nov 2, 2026 · How we score
| Metric | MailerSend | SMTP2GO |
|---|---|---|
| Reliability score | 100.0 | 58.4 |
| Rank (transactional email APIs) | — | #12 |
| Uptime (90 days) | 100% | 99.17% |
| Incidents (90 days) | 0 | 17 |
| Partial / major outages | 0 | 3 |
| Avg time to resolve | — | 5h 39m |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where MailerSend and SMTP2GO differ
- MailerSend reported no incidents in the last 90 days, while SMTP2GO reported 17.
- SMTP2GO had 3 partial or major outages, compared with 0 for MailerSend.
90-day uptime
MailerSend
SMTP2GO
- 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 SMTP2GO incidents
- Degraded performanceOct 30, 2026 · resolved in 10h 12m
Affected: API Servers
- Partial outageOct 15, 2026 · resolved in 2h 20m
Softbounce Errorsofficial update ↗
Affected: Email sending (SMTP service)
- InformationalOct 8, 2026 · resolved in 1h 26m
Issues with API- statusCode=500
Affected: API Servers
- Degraded performanceOct 1, 2026 · resolved in 8h 26m
Affected: Email sending (SMTP service)
- InformationalOct 1, 2026 · resolved in 33m
Connection issues and 'processed' emails
Affected: Email sending (SMTP service)
- InformationalSep 30, 2026 · resolved in 8m
Issues connecting to mail.smtp2go.com
Affected: Email sending (SMTP service)
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 →