Head-to-head
Customer.io vs Mailrelay
Two leading email marketing / automation tools, compared on pricing, features, and editorial fit. Updated for 2026.
At a glance
| Customer.io | Mailrelay | |
|---|---|---|
| Tagline | Messaging that actually fits your data. | Email marketing with a free plan for up to 20,000 contacts |
| Pricing model | Paid | Freemium |
| Starts at | $100/mo | Free |
| Founded | 2012 | — |
| AI-native | ||
| Categories | Email Marketing, Automation | Email Marketing, Landing Pages, Automation |
| Vendor claimed |
Quick take
Pick Customer.io if you need messaging that actually fits your data. Pick Mailrelay if you need email marketing with a free plan for up to 20,000 contacts.
Browse more
Customer.io alternatives →
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Mailrelay alternatives →
Frequently asked
- Is Customer.io better than Mailrelay?
- It depends on your use case. Customer.io is messaging that actually fits your data, while Mailrelay is email marketing with a free plan for up to 20,000 contacts. See the comparison above for which fits your team.
- What's the price difference between Customer.io and Mailrelay?
- Customer.io starts at $100/mo. Mailrelay starts at Free.
- Can I migrate from Customer.io to Mailrelay?
- Most tools in this category support data import via CSV. For complex migrations, both vendors offer onboarding assistance on higher-tier plans.