Apollo.io Inc., founded in 2015 and based in Austin, Texas, offers a comprehensive platform for sales intelligence and engagement. Their key product, Apollo, enables businesses to streamline prospecting, enhance lead generation, and improve sales performance across various industries.
Founded: 2015
Headquarters: Austin, Texas, United States
Revenue: 100m_1b
Employees: 1k_5k
Website: https://www.apollo.io/we-are-apollo
Apollo.io Inc. is a privately held B2B go-to-market software company headquartered in San Francisco, California. The company operates an AI-powered sales intelligence and sales engagement platform that combines a large verified contact database with prospecting, outreach automation, CRM enrichment, and workflow tools in a single product. It serves a broad range of B2B revenue teams, from early-stage startups to large enterprises, and competes in the sales intelligence and sales engagement categories.
Apollo.io Inc. develops and operates an AI-native B2B go-to-market platform built to help revenue teams find prospects, enrich records, automate outreach, and manage deals inside a unified workflow [2]. The company positions its product across two primary MarTech/SalesTech categories: sales intelligence and sales engagement [3]. Core offerings include a contact and company database of 275 million-plus contacts [3], advanced search with 65-plus attribute filters [3], multi-channel outreach sequencing across email, phone, and LinkedIn [3], an integrated dialer with call recording and conversation intelligence [3], AI-assisted email generation and lead scoring [3], CRM data enrichment, inbound lead routing, and workflow automation [2]. The platform is offered under a product-led growth (PLG) model with a free tier and paid plans scaled by seat and credit consumption [2, 27]. Notable enterprise customers cited in the company's 2023 Series D announcement include Qualtrics, Customer.io, and Census [41]; the company's Crunchbase profile also lists Autodesk and Cyera as customers [14].
Apollo.io was founded in 2015 as ZenProspect by Tim Zheng, Roy Chung, and Ray Li in San Francisco [13]. The company was accepted into Y Combinator's Winter 2016 batch, receiving approximately $120,000 in seed funding, and set out to combine a lead database with outbound automation [13]. In 2018, the company rebranded as Apollo.io [13]. After a near-collapse in 2018–2020, including a reported data breach and steep revenue decline, Apollo recovered through a product-led growth strategy built around a freemium, self-serve model [13]. The company raised a $110 million Series C led by Sequoia Capital in March 2022, with participation from Tribe Capital, Nexus Venture Partners, and NewView Capital [45]. On August 29, 2023, Apollo announced a $100 million Series D led by Bain Capital Ventures, with returning investors Sequoia Capital, Tribe Capital, and Nexus Venture Partners, bringing total funding to approximately $250 million and valuing the company at $1.6 billion [42]. In February 2026, Apollo appointed Matt Curl as Chief Executive Officer, with co-founder Tim Zheng moving to Chairman; at that time the company stated it was approaching $200 million in ARR with nearly 100,000 paying customers [13].
Apollo.io operates in the sales intelligence and sales engagement categories, competing across both simultaneously [3]. As of the time of its Series D announcement in August 2023, the company reported serving over 3 million GTM professionals at more than 500,000 companies [42]. By early 2026, the company stated it was approaching $200 million in ARR [13]; a third-party estimate from GetLatka cited $150 million ARR for 2025 alongside a $1.6 billion valuation [11]. On G2, Apollo.io holds a 4.7/5 rating across more than 9,000 reviews as of late 2025 [35], was named a G2 Sales Intelligence Leader in 2025 [39], and ranked #13 in G2's 2026 Best Sales Software awards out of 446 products [40]. In G2's Winter 2026 Report, Apollo appeared in 1,165 reports and earned 624 badges [32]. The platform is cited as particularly strong among SMB and mid-market teams running outbound email-driven prospecting [27]. Enterprise customers mentioned in official press releases include Qualtrics, Customer.io, and Census [41]; Autodesk, ClickUp, and DocuSign are cited in Apollo's G2 and marketing materials [36].
Apollo.io's primary competitors in the B2B sales intelligence and engagement space include ZoomInfo, Cognism, Lusha, RocketReach, Salesloft, Outreach, Seamless.AI, and Clay [3, 26]. Buyers frequently compare Apollo against a combined ZoomInfo-plus-Salesloft or ZoomInfo-plus-Outreach stack, evaluating whether Apollo's all-in-one approach provides sufficient depth at lower cost [3]. ZoomInfo is most often positioned as the stronger choice for enterprise-grade direct-dial phone data, North American data coverage, and Bidstream-powered intent signals, while Apollo is regarded as more accessible for SMBs and startups due to its lower price point and bundled sequencing capabilities [21, 23]. Independent comparisons note that ZoomInfo's entry pricing starts around $15,000 per year, whereas Apollo's paid tiers begin below $100 per user per month [23]. Outreach and Salesloft are positioned as offering deeper sales engagement and pipeline management capabilities than Apollo, but do not include a contact database, requiring buyers to pair them with a data vendor [26]. Cognism is frequently cited as an alternative for teams prioritizing GDPR-compliant European market coverage [24]. Multiple review-platform assessments note that Apollo's data quality for EMEA, APAC, and LATAM contacts is weaker than its US coverage [34, 37].
Apollo.io's G2 rating of 4.7/5 across more than 9,400 reviews reflects a broadly satisfied user base [35]. Reviewers on G2 consistently praise the all-in-one platform approach—prospecting, enrichment, sequencing, and basic analytics in one interface—alongside the accessible per-seat pricing and Chrome extension integration with LinkedIn [39]. A recurring criticism across G2, Capterra, and independent review sites is data accuracy outside the United States: reviewers flag inconsistent mobile numbers and outdated job titles in EMEA, APAC, and LATAM records, as well as email bounce rates that consume credits even for incomplete or inaccurate data [34]. Trustpilot scores are notably lower than G2 at 2.9/5, suggesting a divergence between enterprise and general-consumer reviewer populations [35]. In early 2025, Apollo's LinkedIn company page was removed by LinkedIn; Apollo's CEO stated the removal did not affect the core product, though the episode has been noted as a compliance consideration for buyers who rely on LinkedIn prospecting through Apollo's Chrome extension [39].