Transactional Email APIs · reliability comparison
Mailjet vs SparkPost (Bird): which is more reliable? (2026)
Mailjet is more reliable than SparkPost (Bird), scoring 99.6 vs 87.7 out of 100. Over the last 90 days Mailjet reported 1 incident and SparkPost (Bird) reported 8, with effective uptime of 100% and 99.90% respectively.
Data updated Nov 1, 2026 · How we score
| Metric | Mailjet | SparkPost (Bird) |
|---|---|---|
| Reliability score | 99.6 | 87.7 |
| Rank (transactional email APIs) | #1 | #6 |
| Uptime (90 days) | 100% | 99.90% |
| Incidents (90 days) | 1 | 8 |
| Partial / major outages | 0 | 0 |
| Avg time to resolve | — | 2h |
| Outages we detected | 0 | 0 |
| Transparency score | 100/100 | 100/100 |
Where Mailjet and SparkPost (Bird) differ
- SparkPost (Bird) reported 8× as many incidents as Mailjet over the last 90 days (8 vs 1).
- Mailjet's longest outage on record lasted 32m (Jun 5, 2026); SparkPost (Bird)'s lasted 7h 30m (Jul 24, 2026).
90-day uptime
Mailjet
SparkPost (Bird)
- No incidents
- Degraded
- Partial outage
- Major outage
- No data
Recent Mailjet incidents
- InformationalSep 4, 2026 · resolved in 32m
Recent SparkPost (Bird) incidents
- InformationalOct 30, 2026 · resolved in 22h 2m
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
Affected: SMTP Delivery - USA
- Degraded performanceOct 28, 2026 · resolved in 1h 1m
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
Affected: SMTP Delivery - USA
- Degraded performanceOct 11, 2026 · resolved in 3h 6m
Increased message delays in US and EU due to DNS resolution errors
Affected: SMTP Delivery - USA, SMTP Delivery - EUROPE
- Degraded performanceOct 1, 2026 · resolved in 31m
Affected: SMTP Delivery - USA, SMTP Delivery - EUROPE
- Degraded performanceSep 17, 2026 · resolved in 54m
Outbound message delivery is delayed/slow for some SparkPost customers (US hosted only)
Affected: SMTP Delivery - USA
- Degraded performanceSep 14, 2026 · resolved in 2h 27m
Health Score and Cohort data is delayed
Affected: SparkPost Application - USA, SparkPost Application - EUROPE
Other transactional email APIs to consider
- Mailtrap Email Sending · #2 · 99.99% uptime
- Loops · #3 · 99.98% uptime
- Twilio SendGrid · #4 · 99.98% uptime
- Mailchimp Transactional (Mandrill) · #5 · 99.93% uptime
See the full most reliable transactional email apis ranking →