Waterfall Enrichment

Waterfall enrichment is a data strategy where you query multiple data providers in a predefined sequence — trying the next provider only when the current one fails to return a verified result. This cascading approach dramatically increases data coverage and accuracy compared to relying on a single data source.

For example, to find a verified work email, a waterfall might go: Hunter.io (60% hit rate) → Prospeo (20% incremental) → Dropcontact (10% incremental) → Apollo API (5% incremental) → PDL (final fallback). The result: 90–95% verified email coverage vs ~60–70% from any single provider.

Clay is the most popular tool for waterfall enrichment in B2B sales, connecting to 100+ data providers and letting you build custom waterfall sequences for email verification, phone numbers, LinkedIn data, technographics, and more. The key benefit: you only pay credits when a provider successfully returns data — so the waterfall is cost-efficient even when using many providers.