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Side-by-side comparison

Klaviyo vs Substack

Complaint records and Risk Scores compared. Both are in the Email Marketing category.

✓ Substack has a lower documented Risk Score. Substack's Risk Score of 20 is lower than Klaviyo's 33. That said, always read the full complaint records before deciding.
Product A

Klaviyo

E-commerce email and SMS platform with rapidly-escalating pricing

33
Mixed Signals
out of 100
2 documented warnings
Email Marketing
Full Klaviyo record →
✓ Lower risk
Product B

Substack

Newsletter and podcast platform that takes 10% of paid subscription revenue

20
Mixed Signals
out of 100
2 documented warnings
Email Marketing
Full Substack record →

Complaint category breakdown

Higher numbers in each row indicate more documented complaints in that category. Bold = more complaints than the other product.

Complaint type Klaviyo Substack
BBB Complaints — —
Lawsuits & Legal Action — —
Misleading Marketing — —
Customer Complaints 1 1
Churn & Retention — —
Billing Problems 1 1
Support Failures — —

Severity breakdown

Severity Klaviyo Substack
Critical — —
High 1 —
Medium 1 1
Low — 1

Read the full records

Klaviyo full review → Substack full review → Klaviyo complaints → Substack complaints →