Google Ads has changed the game by allowing advertisers to use audiences with as few as 100 users. Earlier, marketers needed much larger lists. Now, even small businesses and niche brands can run highly targeted campaigns and get strong results.

In this article, we share real-world style case studies that show how small audience campaigns can still deliver high ROI, conversions, and growth.

What Is the 100-User Audience Rule in Google Ads?

Google now allows:

  • Remarketing
  • Customer Match
  • Audience Insights

to work with lists starting from 100 users across Search, Display, and YouTube.

Why Small Audiences Are Powerful Now

Smaller audiences mean:

  • More personalization
  • Higher relevance
  • Better conversion rates
  • Lower wasted ad spend

Google’s AI and Smart Bidding can now optimize even with limited data.

Strategy Framework for 100-User Campaigns

  1. Use first-party data (email, CRM, website visitors)
  2. Segment users by intent (buyers, cart abandoners, repeat visitors)
  3. Create hyper-relevant ad copy
  4. Use Smart Bidding (Max Conversions / Target CPA)
  5. Keep budgets focused, not broad

Case Study 1: Local Service Business

Business: Home Cleaning Service (City Level)
Audience Size: 140 past website visitors
Campaign Type: Search Remarketing

Result:

  • Conversion Rate: 12.4%
  • Cost per Lead: 35% lower than cold traffic
  • Booking Rate increased by 2X

Reason for Success:
Users already knew the brand. Personalized ads with “Book Again & Get 10% Off” worked perfectly.

Case Study 2: E-Commerce Brand

Business: Niche Fitness Accessories Store
Audience: 120 Cart Abandoners
Campaign: Display + YouTube Remarketing

Result:

  • ROAS: 4.1X
  • Recovery of abandoned carts: 28%
  • High repeat purchase rate

Reason:
Video ads showing product usage created trust and urgency.

Case Study 3: B2B Lead Generation

Business: SaaS Tool for Accountants
Audience: 100 CRM Leads
Campaign: Customer Match on Search

Result:

  • Lead Quality improved
  • Demo Booking Rate: +40%
  • Sales Cycle shortened

Reason:
Exact match of decision-makers using problem-solution ad copy.

Smart Bidding with Small Data Sets

Best bidding strategies:

  • Maximize Conversions
  • Target CPA
  • Enhanced CPC

Google’s machine learning now adapts even with limited audience signals.

Creative & Message Personalization

Tips:

  • Mention user pain points
  • Use dynamic headlines
  • Add trust signals (reviews, years of experience)
  • Focus on benefits, not features

Key Metrics to Track

  • Conversion Rate
  • Cost Per Conversion
  • Impression Share
  • Frequency
  • ROAS
  • Engagement Rate

Common Mistakes to Avoid

  • Using broad keywords with small lists
  • Running generic ad copy
  • Low budget with high bid strategy
  • Not refreshing creatives
  • Ignoring frequency capping

How This Connects with Google Lowering Audience Size Limits

Google’s decision to reduce minimum audience size has:

  • Empowered small advertisers
  • Improved remarketing reach
  • Increased first-party data value

Read full update here: Google Lowers Audience Size Limits Across Ads

Key Takeaways

  • 100-user audiences can be highly profitable
  • Personalization is the main growth driver
  • Smart Bidding works even with micro data
  • First-party data is now more powerful than ever