Apollo.io vs Seamless (2026)

Apollo.io

by Apollo

Seamless

by Seamless.AI

Pros

• ✓240M+ verified contacts and 30M+ companies with filters for funding stage, technographics, hiring signals, intent data, job change alerts, and AI-powered Lookalikes (BETA), all without a separate data provider.
• ✓Autonomous sequence execution runs outreach end-to-end once configured: Apollo sends, waits, follows up, and logs to CRM without per-step human approval. AI Assistant (introductory free on paid plans) provides conversational access to prospecting data and campaign analysis.
• ✓Publishes a first-party remote MCP server at mcp.apollo.io with OAuth and prebuilt connectors for Claude, ChatGPT, and Perplexity, available on every plan including the free one, plus action-level CRM writes to Salesforce and HubSpot.
• ✓Bidirectional CRM sync is documented for both Salesforce and HubSpot, keeping records consistent in both directions rather than one-way export, and Apollo's AI policy states that data flowing through customer-configured AI integrations is not used for its own model training.

Limitations

• –Real cost depends on credit use. Credits are granted upfront on annual plans and additional credits are bought separately, with a verified email costing 1 credit, a phone number 8 credits, data enrichment 1 to 8 credits per record, and US dialing 2 credits per minute.
• –API call limits depend on the plan: Free runs at trial-level limits, Basic and Professional allow 2,000 calls per day, Organization allows 6,000, and higher limits require a Custom plan through sales.
• –Organization requires a minimum of 3 seats at $119/user/mo and is sold Annual Only, so unlike Basic and Professional it cannot be bought month to month. Downgrades take effect immediately with no mid-term refunds, so teams that shrink pay for the remainder of their billing cycle on unused capacity.
• –Apollo's AI policy states that Apollo may use Customer Data as an input to train its own internal models, and publishes no customer opt-out. The only opt-out offered is profile suppression for individuals in Apollo's contributor database, which is a data-subject right rather than a customer control.

Pros

• ✓Real-time search engine produces fresher data than aggregated databases: Seamless finds contact data at the moment of search across 1.6B+ verified emails and 448M+ phone numbers, materially better cell phone freshness than ZoomInfo or Apollo for connect-rate-sensitive outbound.
• ✓5,356 G2 reviews at 4.4/5 is one of the largest review bases in B2B sales software: exceptional independent validation that provides procurement confidence no smaller competitor can match, with 1M+ sales leaders using the platform.
• ✓Platform expanding from data-only to full revenue engine: Data Engine, Engagement Hub, AI Agents, and Automation Network give teams a path to consolidate prospecting and engagement in one platform, reducing multi-vendor complexity over time.

Limitations

• –Sales-led pricing for paid tiers creates evaluation friction: published prices only for the Free tier (50 credits) means lengthier procurement cycles than transparent-pricing competitors such as Apollo.io, which publishes per-tier pricing publicly.
• –Engagement Hub and AI Agents are newer capabilities still maturing: Seamless is historically a data platform and the Connect, AI Agents, and Automation features are earlier in development than dedicated engagement platforms like Outreach or Salesloft.
• –Free tier reduced from 1,000 to 50 credits: the current free tier is significantly more limited than it was historically, which reduces the evaluation window for teams testing before committing to a sales conversation.