• Growth Elements
  • Posts
  • $0 CAC Playbook: How Modern Startups Grow Without Paying for Traffic

$0 CAC Playbook: How Modern Startups Grow Without Paying for Traffic

Author

Chintankumar Maisuria
April 10, 2025

Read time: 3 minutes.

Welcome to the 109th edition of The Growth Elements Newsletter. Every Monday and sometimes on Thursday, I write an essay on growth metrics & experiments and business case studies.

Today’s piece is for 7,500+ founders, operators, and leaders from businesses such as Shopify, Google, Hubspot, Zoho, Freshworks, Servcorp, Zomato, Postman, Razorpay and Zoom.

Today’s The Growth Elements is brought to you by:

The Secret to Turning Products Into 7-figure Listings.

Scale your Amazon growth by driving high volume sales and improve your listing’s search positioning. Using Stack Influence’s unique platform, brands like Magic Spoon, Unilever, and Farmacy have increased their monthly revenue as high as 13X in as little as 1 month.

Some of the benefits for sellers are:

  • Increase Amazon listing search positioning (drive high volume external traffic sales)

  • Pay influencers only in products (stop negotiating fees with every influencer)

  • Generate branded image/video UGC with full legal rights (no timeframe or usage restrictions)

  • Develop affiliate relationships (easily identify top influencer candidates to work with in the long run)

  • Automate influencer collaborations from A-Z (save over 175 management hours per month)

Thank you for supporting our sponsors, who keep this newsletter free.

Startups love to talk about CAC.

But what if you didn’t have to pay for it at all?

We’re seeing a new wave of companies growing with $0 paid acquisition, no Google Ads, no paid social, no outbound SDRs. Just product loops, shareable experiences, and channels that scale on their own.

This isn’t about avoiding growth spend—it’s about building distribution directly into the product.

And it’s forcing a rethink of how we define go-to-market.

What $0 CAC Actually Means

CAC is often misunderstood.

$0 CAC doesn’t mean free growth; it means the acquisition channel is built into usage, not layered on top of spend.

Here’s how it plays out:

  • Distribution is embedded into user behaviour

  • Growth is fueled by network effects, not ad impressions

  • Activation, engagement, and virality happen in-product, not in campaigns

Tactics That Power $0 CAC Growth

[1] Side Products That Feed the Funnel

Startups are building tools that rank, get shared, or solve micro-problems and drive traffic to the main product.

  • Ahrefs: Free SEO tools like keyword generator and backlink checker

  • Beehiiv: Newsletter idea generator -> feeds back into their main platform

  • OpenAI: ChatGPT became a growth loop for its API product

Side products don’t sell—they distribute.

[2] Built-in Virality

Some products don’t need a sales team because users do the selling.

  • Figma: Every design shared is a new user touchpoint

  • Notion: Templates, embeds, and team invites drive constant loops

  • Calendly: Every booking link is a mini viral node

  • Loom: View a video - > sign up to comment or record your own

If every action creates a new exposure, you don’t need paid growth.

[3] Content as Distribution

Not SEO spam. Actual, helpful, scalable content that drives sign-ups.

  • Linear: Changelog, docs, and updates that feel like a product release

  • Replit: Developer tutorials double as onboarding

  • Mistral AI: Grows through deep technical write-ups + OSS credibility

Content isn’t marketing. It’s product education at scale.

[4] AI-Led Discovery Channels

In 2025, users are asking ChatGPT, Perplexity, and Gemini to recommend tools.

  • “What’s the best free AI scheduling tool?”

  • “Give me three alternatives to Notion for team wikis.”

  • “What’s the easiest way to record async videos?”

If you’re not optimized for AI-surfaced discovery, you’re invisible.

Write like you’re answering a prompt, not pitching a feature.

[5] Powered by Community, Not Campaigns

Startups today embed into communities that already exist instead of building from scratch.

  • Indie Hackers

  • X / Threads

  • Founder Slack groups

  • WhatsApp loops

  • Private Notion hubs

This is dark social GTM; you won’t find the link in your attribution model, but it converts better than paid.

What $0 CAC Startups Have in Common

Strategy

Outcome

Built-in loops

Every action drives new users

Shareable moments

Output = exposure

No hard paywalls upfront

Product speaks before the pricing page

AI-surfaced answers

Indexed in AI, not just Google

Community-native messaging

Distribution through trust

Final Words

  1. Paid traffic is a tax on poor distribution and product design.

  2. Startups with $0 CAC don’t “hack” growth, they build it into the product.

  3. If you need to pay to explain what your product does, it’s not ready for scale.

  4. Today’s best acquisition channel? The user’s behavior itself.

That's it for today's article! I hope you found this essay insightful.

Wishing you a productive week ahead!

I always appreciate you reading.

Thanks,
Chintankumar Maisuria