Apollo.io

Apollo is a B2B contact database plus an outbound email sequencer rolled into one platform. The database covers tens of millions of professional contacts with email addresses, phone numbers, and buyer intent signals.

It does in one tool what used to take three. Contact data came from one vendor, sequence sending from another, intent signals from a third. Apollo combined them into a single subscription with a single contact view.

AI-assisted sequencing writes personalized opening lines based on prospect data, and intent data shows which target accounts have been researching topics in your category recently. The personalization quality varies by how much public information exists on each prospect, so review before sending in volume.

The free tier is unusually generous for the category. It includes monthly credits and access to most of the database, enough to actually evaluate the product on real outbound work rather than a demo-shaped trial.

Common workflows by role:

• SDRs build prospect lists and run multi-touch sequences in one tool
• Demand gen teams export contact data to ad platforms for lookalike audiences
• Founders running their own outbound at early-stage scale
• Recruiters using the same contact data for candidate sourcing

A few specifics worth knowing:

• Contact data is sourced and verified through Apollo's own systems
• Email send infrastructure is included, not bolted on through a separate sender
• LinkedIn extension pushes prospects from search results into sequences in two clicks
• Intent signals flag accounts that are researching relevant topics

Apollo integrates with the rest of the stack through:

• Salesforce and HubSpot for CRM sync
• Outreach and Salesloft for teams running separate engagement platforms
• LinkedIn through the browser extension
• Zapier for everything else

Data coverage is strongest for North American and European mid-market companies. It's thinner in other regions, which matters if your ICP is APAC or Latin America. Most teams using Apollo are targeting US and European B2B.

Apollo is the simplest fit for volume-driven outbound where contextual signals matter less. For sales motions where contextual research per prospect matters more, and where the budget supports it, Clay sits at the more sophisticated end of the same category.

Freemium model with a free tier including monthly credits, scaling to paid subscription per seat with higher credit limits and team features.

Best for B2B marketers and SDRs running outbound at growth stage who need extensive contact data without enterprise-level pricing. Not ideal for B2C marketing or for teams where data quality and signal richness matters more than volume.