📧 Email & Communication Comparison
Customer.io vs Userlist
A detailed comparison to help you choose the right tool for your needs.
Last updated: 2026-02-05
Customer.io
From $100/mo
Strengths
- + Powerful segmentation
- + Multi-channel (email, SMS, push)
- + Great for product-led growth
Weaknesses
- − Expensive for small lists
- − Steep learning curve
Userlist
From $99/mo
Strengths
- + SaaS-focused (not generic marketing)
- + Behavior-based campaigns
- + Company-level tracking
Weaknesses
- − Pricier than generic tools
- − Smaller ecosystem
The verdict
Which one is right for you?
Choose Customer.io if you want
- → Powerful segmentation
- → Multi-channel (email, SMS, push)
Choose Userlist if you want
- → SaaS-focused (not generic marketing)
- → Behavior-based campaigns
In depth
About each tool
Customer.io
Behavior-based email and push for SaaS
Customer.io sends messages based on what users actually do in your product. Founded by Colin Nederkoorn, “fundstrapped” (took some money but runs like bootstrapped). Took 18 months to hit $10k MRR, now at $100M ARR. Great for SaaS doing product-led growth.
Userlist
Email automation built specifically for SaaS
Userlist is email automation that actually understands SaaS. Track users AND companies, trigger emails based on product usage, run onboarding sequences that adapt to behavior. Built by Jane Portman and Benedikt Deicke specifically because generic email tools don’t get SaaS.
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