Bull case
Klaviyo is supported by durable core demand, evidenced by 2Q26 revenue of $370.6 million (+26.4% y/y), 3Q26 revenue of $379.3 million (+22.0% y/y), and FY26 revenue guidance lifted to about $1.53 billion (+24.0% y/y), showing that growth remains strong even as the business scales. Its outlook is reinforced by clear product and monetization expansion: Composer reached 95K users in its first month, Customer Agent adoption rose 40% sequentially in 2Q, personalization-related data and analytics ARR grew 100% y/y, and larger customers now represent 40% of ARR with 36% y/y growth. Although gross margins compressed to 73.4% and PF EBIT margins eased to 11.0% in 3Q26 and 14.0% for FY26, higher usage, lower CAC, better retention, and stronger cross-sell suggest these tradeoffs are fueling a broader platform with improving long-term expansion potential.