Sierra is raising $950 million led by Tiger Global and GV at a valuation of more than $15 billion, co-founders Bret Taylor and Clay Bavor wrote on 4 May 2026. The company said the round brings investable capital above $1 billion and will fund scaling of customer-experience AI agents.
Sierra said it has grown from four design partners a couple of years earlier to serving over 40% of the Fortune 50, with agents powering billions of interactions. Use cases now extend beyond support into insurance first notice of loss, claims and sales, home lending, banking offers, healthcare revenue cycle, telecoms and retail.
Named launch examples in the founders’ post include Nordstrom’s Nora voice agent delivered in five weeks; Singtel in ten weeks with resolution rates the company put above 70%; and Cigna in eight weeks with patient authentication claimed 80% faster. All performance figures are Sierra’s. Valuation language and Fortune 50 penetration are likewise company claims.
Taylor and Bavor framed the raise as fuel to keep shipping agents that handle complete customer workflows rather than single-turn chat scripts.
Investable capital above $1 billion, if completed on the terms described, would place Sierra among the best-capitalised pure-play CX agent vendors.