Apollo.io is a B2B sales intelligence and engagement platform founded in 2015 (as ZenProspect) by Tim Zheng, Roy Chung, and Ray Li, and backed by Y Combinator. It rebranded to Apollo.io in 2018 and reported roughly $150M ARR (May 2025) at a $1.6B valuation set in its August 2023 Series D; in May 2026 the company said revenue had grown more than fivefold since that round, though no exact current figure is disclosed. The platform is headquartered in San Francisco.
The core product combines a 275M+ contact (73M+ company) database with built-in outreach tooling — email sequencing, a sales dialer, LinkedIn automation, and CRM enrichment — in a single self-serve interface. This all-in-one positioning makes it a popular alternative to stitching together ZoomInfo for data, Outreach/SalesLoft for sequencing, and a separate enrichment tool.
In March 2026 Apollo brought its AI Assistant to general availability (after a beta that opened in October 2025), positioning it as an end-to-end agentic GTM layer: reps drive prospect discovery, enrichment, outreach and reporting through natural language. The company reports roughly 20,000 weekly users and that beta users booked ~2.3x more meetings. In practice it remains "draft-and-approve" rather than fully autonomous, but it is meaningfully more capable than the late-2025 beta.
Apollo's biggest real-world limitation is data quality: email bounce rates of 15–30% are common, phone number accuracy is notably weaker, and international coverage is meaningfully worse than US coverage. The credit-based pricing model is also a common frustration, as actual per-user costs frequently exceed the advertised plan price once overages and add-ons are factored in.
Key Benefits
- Database breadth: 275M+ contacts filterable across 60+ firmographic and technographic attributes, making list-building faster than most alternatives at the same price point.
- Reduced tool sprawl: Prospecting, sequencing, dialing, and enrichment in one platform cuts subscription costs and context-switching for smaller teams.
- Accessible entry point: The free tier provides enough credits for early validation, and the Basic plan at $49/month is well below legacy data providers.
- CRM-native enrichment: Native Salesforce and HubSpot sync keeps contact records up to date without a separate enrichment workflow.
- Embedded AI features: The 2025 AI Assistant speeds up account research and draft generation within the existing workflow rather than requiring a separate tool.
Use Cases
- Outbound SDR prospecting — Sales reps build targeted lead lists using Apollo's filters, verify contact details, and launch multi-step email or LinkedIn sequences without leaving the platform.
- CRM data enrichment — RevOps teams upload existing contact lists or connect Salesforce to auto-fill missing firmographic fields, job titles, and verified emails.
- Account-based marketing list building — Marketing teams identify ICPs by technology stack, headcount, funding round, or hiring signals to feed campaigns with pre-qualified accounts.
- Pipeline coverage for lean teams — Early-stage startups without a dedicated sales stack use Apollo as their single outbound tool, combining prospecting and engagement in one affordable subscription.
