140M visits lost, 10x conversion gains: HubSpot’s AI growth playbook - Kieran Flanagan [HubSpot]

Today on BILLIONS, I’m sitting down with Kieran Flanagan, SVP of Agentic GTM & Systems at HubSpot.

Kieran spent 10 years helping build one of the most copied growth engines in SaaS, left to become CMO of Zapier, and then came back to HubSpot to help rebuild its entire go-to-market playbook around AI.

And they had no choice but to rethink it.

In just one year, HubSpot lost 140 million visits — around 80% of its organic traffic — as Google and AI completely changed how people search.

Yet the company kept growing.

Some of HubSpot’s AI-powered experiments increased conversion rates by 3x, 5x, and even 10x.

Today, HubSpot serves more than 300,000 customers, generates more than $3B in revenue, and is rebuilding the growth engine that made it famous for an AI-first world.

In this masterclass, we break down:

→ How HubSpot lost 80% of its organic traffic and still kept growing

→ The AI experiments that generated up to 10x conversion improvements

→ Why Kieran believes informational SEO is being killed by AI

→ How HubSpot is optimizing for ChatGPT, Gemini and answer engines

→ Why “taste and judgment” are becoming more valuable as AI gets better

→ How to build context layers that make AI agents smarter over time

→ Why junior employees may actually struggle more with AI than experts

→ How HubSpot built a network of 350 creators to replace part of its search-driven growth

→ Why some shows inside that network grew 5x

→ How more than half of HubSpot’s revenue now comes from customers who started as free users

→ The new distribution channels and ecosystems HubSpot is betting on next

We also discuss why AI is creating a “sea of sameness”, why perfectly polished content can now be a disadvantage, how creators can influence visibility inside AI engines, and what happens to Google when users no longer need to click on links.

If you want to understand how one of the biggest growth companies in SaaS is rebuilding its playbook for the AI era, this is the episode.

TIMELINE:

00:50 – Building a billion-dollar company before vs. after AI03:14 – Using AI to personalize emails at scale05:40 – How HubSpot lost 140M organic visits08:26 – The new AI-first marketing playbook11:55 – Building taste and judgment into AI15:12 – Kieran’s AI Content OS18:11 – Why AI-generated content all looks the same23:48 – Replacing SEO with new distribution channels25:28 – HubSpot’s 350-creator network27:18 – How this creator network works?31:28 – Winning inside ChatGPT and answer engines34:50 – HubSpot’s next big growth bets37:10 – AI, agencies and HubSpot’s partner ecosystem39:28 – Kieran’s new book, Loop