Waterfall enrichment: how we find and verify contacts
Why no single data provider is enough, how we order providers in a waterfall, and the verification step that keeps bounces down.
No single data provider has everyone. Each one is strong in some regions, company sizes and roles, and weak in others. A waterfall asks providers one after another until it finds a verified result, so you get the coverage of several tools and only pay for the lookups you need.
How a waterfall works
- Start with the provider that has the best hit rate for this segment at the lowest cost.
- If it returns nothing, or a result that fails verification, move to the next provider.
- Stop at the first verified result.
- Verify again before the contact reaches a sequencer.
We build these in Clay, with providers such as Prospeo, LeadMagic, BetterContact and Findymail, and verification tools at the end of the chain.
Ordering the providers
The order is not fixed. For US SaaS contacts one provider usually wins; for Indian mid-market companies or GCC enterprises a different one does. We test on a sample of each new segment before running the full list, and reorder by cost per verified contact.
The verification step
Finding an address is not the same as knowing it is safe to send to. Catch-all domains in particular accept every address, so they look valid until they bounce or, worse, quietly hurt your reputation. We treat catch-all results as a separate tier and send to them more cautiously.
Beyond email addresses
The same pattern works for any data point: phone numbers, company technographics, headcount trends or a research question answered by an AI agent. Ask the cheapest reliable source first and only escalate when you need to.