Sierra

Sierra is an enterprise AI customer service platform co-founded in 2023 by Bret Taylor and Clay Bavor. Taylor is a former Salesforce co-CEO, co-creator of Google Maps, and OpenAI board chair, and Bavor is an 18-year Google veteran who led Google Labs, Lens, and Workspace. Sierra builds conversational AI agents that handle complex, multi-turn customer service interactions autonomously across voice, chat, and digital channels. The agents connect to CRMs, order management systems, subscription platforms, and data warehouses to complete actions rather than only answer questions. As of Q3 2026, Sierra has raised $1B+ in total funding at a $15.8B valuation and reports $150M+ ARR, with the first $50M quarter delivered in February 2026. Sierra serves 40% of the Fortune 50. Half of its customers have revenue exceeding $1B and one in four exceeds $10B. Deployed by ADT, SiriusXM, Sonos, WeightWatchers, Rocket Mortgage, SoFi, Chime, Brex, Ramp, Cigna, Sutter Health, R1 RCM, Redfin, Casper, Nordstrom, Vanguard, Santander and FINRA. Ghostwriter, launched March 25, 2026, lets enterprise teams upload SOPs, call transcripts, whiteboard photos, or audio recordings, or describe a goal in plain English. It then produces a production-ready agent across voice, chat, and email without requiring engineering resources to configure from scratch. Sierra publishes no connector marketplace and no pre-built integration library, verified against six candidate paths in September 2026. Integrations are custom API work scoped during the implementation engagement, and the platform connects to data warehouses including Snowflake, Databricks, Google Cloud and Redis. Channels include voice, chat, email and WhatsApp, in 59 languages. Since October 2025 customers can publish an agent into ChatGPT with one click, exposing that agent to ChatGPT over the Model Context Protocol, with the customer choosing which journeys, data and capabilities are shared. That route is scoped to ChatGPT Apps, and Sierra documents no MCP endpoint for other clients such as Claude or Cursor. Pricing is outcome-based and fully custom. Sierra charges per resolved outcome rather than per seat or conversation, and publishes no pricing page and no rate card, so all commercial terms are negotiated directly. Sierra publishes no minimum commitment, no platform fee and no per-outcome rate on any public surface. The outcome-based model ties what a buyer pays to resolution volume, and the definition of a resolved outcome and the per-outcome rate are both contract-negotiated terms, so budget modeling requires a commercial discussion. Sierra is sold to large enterprises and deployment is a sales-led engagement rather than a self-serve signup. Configuring API connections and mapping customer workflows takes dedicated engineering support, and integration changes route through Sierra's team rather than self-service configuration. Published customer timelines run from two weeks to ten weeks to go live. Teams that want a self-serve starting point with a published connector library can look at Intercom Fin, which starts at $0.99 per outcome. Teams that want AI layered onto an existing help desk they already run can look at Zendesk AI. Current state Q3 2026: Sierra closed a $950M Series E at a $15.8B valuation on May 4, 2026, led by Tiger Global and GV. Sierra was certified FedRAMP High on June 10, 2026 in partnership with Knox Systems, the federal standard for cloud companies working with U.S. government agencies. The compliance posture also covers SOC 2 Type II, ISO 27001, ISO 42001, HIPAA, GDPR and CCPA, with CSA STAR Level One self-assessment, PCI DSS 4.0.1 and an EU AI Act listing shown on the trust center. Sierra opened a Toronto office in May 2026 with about a dozen employees. Ghostwriter reached general availability in Q1 2026 and ARR crossed $150M in February 2026. On July 16, 2026 Sierra announced Horizon, a platform for long-horizon agents pursuing multi-step goals such as loan origination, prior authorization or closing a sale over days to months. It layers long-horizon planning and a context engine onto Agent OS. On July 23, 2026 Sierra acquired Takeoff, a long-horizon agent runtime built by a three-person team over 14 months, and the combined teams are building Horizon.