series-b

Series B Stack

Series B B2B SaaS scaling from $5M to $15M ARR. 5–10 SDRs plus an AI-SDR layer (Claude-powered) running tier-2 accounts, mid-market ICP expansion, dedicated revenue ops. CRM still HubSpot Pro; orchestration handled in n8n.

Stack Tools

  • Clay $149/mo
  • Smartlead $39/mo (Basic, 2,000 active leads)
  • HubSpot $15/mo per seat (Starter CRM, annual) — free CRM tier also available
  • RB2B $0/mo (Free tier, up to 100 visitor IDs/mo); paid plans from ~$149/mo
  • Apollo $49/mo (Basic, annual)
  • HeyReach $79/mo (Starter, 1 LinkedIn account)
  • Factors.ai ~$399/mo (Growth plan, estimated; custom enterprise pricing available)
  • 11x ~$5,000/mo (estimated; pricing not publicly listed)
  • n8n $20/mo (Starter, cloud-hosted, 2,500 workflow executions); $0 self-hosted
Estimated monthly cost $10,000/mo

The Series B stack adds the AI-SDR layer that pre-Series-A teams cannot economically justify. The same Clay + Smartlead + HubSpot core scales up; 11x or Artisan handles tier-2 outbound at machine throughput while human SDRs move up to tier-1 named accounts. Factors.ai becomes load-bearing as the revenue ops function matures.


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