Case Study: Pair of Thieves achieves 8.5x list growth and 42% of revenue from email with Klaviyo

How MuteSix helped Pair of Thieves increase their YoY revenue by 5x using Klaviyo alongside Facebook advertising

Pair of Thieves, a growing underwear and socks brand that gained viral attention but saw limited sales lift, needed to capture more market share in a crowded category. With only about 10,000 email subscribers and basic Facebook and Mailchimp efforts, the company wanted to acquire more buyers, retain customers, and drive sustainable revenue growth against larger competitors.

Working with agency partner MuteSix, Pair of Thieves moved email from Mailchimp to Klaviyo and implemented a full-funnel strategy that paired targeted Facebook ads with Klaviyo segmentation and automated email flows. Tactics like a high-converting full-screen pop-up (15% conversion) grew the list to 85,000 (8.5x), helped deliver a 5x year-over-year revenue increase, and drove major ROI: 42% of revenue from email, 25% from automated flows, and a reported 60x return on Klaviyo spend.

Pair of Thieves

Cash Warren

Co-Founder