
VS

Two transactional email providers, compared on price, features and ratings — so you can pick fast.
Updated June 2026
The verdict
Customer.io and Mandrill take different pricing approaches. Customer.io rates higher with developers (4.4 vs 4.2 on G2). Pick based on volume and team — the scorecard below breaks down where each one leads.
By the numbers
Leader highlighted · figures as of June 2026
G2 rating · out of 5
4.4
Customer.io
4.2
Mandrill
Trustpilot · out of 5
3.2
Customer.io
1.6
Mandrill
Drag-and-drop editor · visual builder
Yes
Customer.io
No
Mandrill
Scorecard
| Capability | ![]() | ![]() |
|---|---|---|
| Pricing | ||
| Starting paid plan | $100/mo | $20/mo |
| Cost per 1k @ 100k | — | $0.8 |
| Pricing model | Subscription | PAYG |
| Overage | Profile-based pricing: additional profiles $0.009 each; additional emails $0.12 per 1,000 over the plan's bundled allowance; AI credits $10/100K. Email volume does not map to a per-email tier. | Auto-purchase blocks or stop sending; no rollover |
| Deliverability | ||
| Dedicated IP | Plan-gated | Add-on |
| Deliverability tooling | Yes | Yes |
| Automated IP warmup | Yes | Yes |
| Suppression management | Yes | Yes |
| SPF / DKIM / DMARC | Yes | Yes |
| API & sending | ||
| Transactional API | Yes | Yes |
| Marketing campaigns | Yes | Yes |
| SMTP relay | No | Yes |
| Inbound routing | No | Yes |
| Dynamic templates | Yes | Yes |
| Batch send | Yes | Yes |
| Scheduled send | Yes | Yes |
| Developer experience | ||
| Official SDKs | Ruby, Python, Node.js, Go, PHP, JavaScript (Web), iOS, Android, React Native, Flutter, Expo | PHP, Python, Ruby, Node.js, JavaScript |
| Event webhooks | Yes | Yes |
| Drag-and-drop editor | Yes | Yes |
| Custom HTML editor | Yes | Yes |
| Email validation | No | No |
| Sandbox / test mode | — | Yes |
| Analytics | ||
| Open / click tracking | Yes | Yes |
| Analytics dashboard | Yes | Yes |
| A/B testing | Yes | Yes |
| Compliance | ||
| EU data residency | Yes | No |
| SOC 2 | Yes | Yes |
| HIPAA | Yes | No |
| GDPR | Yes | Yes |
| ISO 27001 | Yes | Yes |
| Support | ||
| Support channels | Community + email (Essentials); chat (Standard); dedicated CSM + technical specialist (Premium/Enterprise) | Email, Chat |
| Support SLA | Plan-gated | Plan-gated |
| Migration assistance | Yes | — |
Decision helper


FAQ
Customer.io rates higher on G2 (4.4 vs 4.2). Ratings are aggregated from public review platforms as of the date shown.
Keep comparing
Why not both?
Route Customer.io, Mandrill, or both — and switch providers without changing your code. Courier sits in front of every channel.
Pricing, plans and feature availability as of June 2026 and may change. Ratings are aggregated from public review platforms. Mandrill is Mailchimp Transactional.
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