How Similar Segments Works
Similar segments are algorithmically generated by Google based on shared behavioral signals between a seed audience (remarketing list, Customer Match list) and users not in that list. Google analyzes search behavior, content consumption, and website visit patterns to find users who exhibit patterns statistically similar to the seed audience. Important context: Google deprecated similar audiences in August 2023, replacing them with AI-powered Smart Bidding and optimized targeting features within Performance Max and standard campaigns. Advertisers who relied on similar audiences now access equivalent functionality through Google's AI optimization layers rather than manually applied audience segments.
Why Similar Segments Matters for B2B Marketing
For B2B advertisers pre-deprecation, similar segments built from converted lead lists or closed-won customer lists were highly effective for prospecting — finding new users who matched the behavioral fingerprint of actual buyers. Post-deprecation, the equivalent strategy is using Smart Bidding with strong conversion data and optimized targeting enabled, which allows Google's algorithm to find and bid on impressions likely to convert based on patterns learned from your conversion history. The quality of your conversion tracking directly determines the quality of algorithmic prospecting.
Similar Segments: Best Practices & Strategic Application
Post-deprecation best practices for B2B similar audience strategies include: ensuring conversion tracking captures the full value of different conversion types (lead form, demo request, phone call, chat) with accurate conversion values to train Smart Bidding properly, using Customer Match lists as seed signals within Performance Max campaigns to guide audience expansion toward users similar to your best customers, enabling optimized targeting on Display campaigns to allow Google to expand beyond strict audience boundaries toward predicted converters, and regularly feeding fresh Customer Match data to maintain the quality of algorithmic seed signals.
Agency Perspective: Similar Segments in Practice
MV3 Marketing transitioned clients from similar audience reliance to Smart Bidding + optimized targeting workflows when Google deprecated the feature. The key to maintaining prospecting performance is conversion data quality — we audit conversion tracking before any audience expansion campaign launch to ensure the algorithm has clean, comprehensive signals to learn from.
