What is waterfall enrichment?

Waterfall enrichment means querying multiple data providers in sequence, so each one fills the gaps the previous provider missed. Instead of trusting a single source, you cascade through several to maximise coverage and accuracy.

The payoff is data quality: waterfall enrichment typically pushes valid-email coverage to around 85–95%, versus 50–70% from a single source. Since bad data burns sender reputation and wastes touches, this is one of the highest-leverage steps in building a prospect list.