Data Append Fill Rates, Match Rates, and Waterfall Matching

Understanding fill rate and match rate

Before we dive into methodology, it’s important to define the two key metrics we use to evaluate data append performance:

• Match Rate: The number of records in your file that matches the provider’s ID space.
  • Resonate’s typical match rate for HEMs: 40–60%
• Fill Rate: The percentage of data that can be fulfilled by a data provider against a customer’s file, such as a CRM file. Fill rate may also be known as data coverage or data density.
  • Resonate’s target fill rate: 100% on matched IDs

Think of match rate as "how many IDs we can connect,” and fill rate as “how complete those connected records are.” Together, these determine the value of your Appended dataset.

How our precision-focused matching works: Waterfall matching method

To ensure you get the best possible match results for Resonate Append, Resonate uses a waterfall matching methodology. This process increases the chance of a successful match without compromising data quality.

At Resonate we understand the importance of individual level predictions and the role it plays in enriching customer’s file. Let’s dive into how we achieve this.

What is Waterfall Matching?

Waterfall matching for Resonate Append, means we start by trying to match your data using the most precise, highest-confidence individual-level identifiers first (like HEMS and MAIDs), then cascade down to next most reliable and precise identifiers in order of the strongest available data to match people who were not already matched in preceding steps. This process ensures we’re matching as many records possible, while still delivering the highest match quality.

We start with a direct match pairing your provided ID to the corresponding ID in our database. If there isn’t an available match at that level, we move down the line to other valid individual-level identifiers. And from there, we proceed to more approximate, household-level matching.

Here’s a simplified example:

By starting with the most accurate individual-level identifiers and moving to the next-best, we ensure you get the strongest possible connection—not just a convenient one.

We also believe you should have full transparency and visibility around our matching, which is why our output indicates the ID used for matching. This also helps validate accuracy and explain any insight expansion that may occur.

Why this approach matters

Though some providers take a “match at all costs” approach, Resonate focuses on what matters most: quality, reliability, and actionability.

Individual-level predictions offer the highest precision because they’re built from a single person’s behaviors, preferences, and intent signals. This means you can:

• Target more effectively
• Segment more intelligently
• Personalize messaging that resonates
• Predict future actions with confidence

In contrast, household-level predictions are built on shared or inferred behavior across people living at the same address. While still useful, they may lead to a more generalized messaging and slightly lower accuracy.

But here’s the key: Even if you don’t have individual-level identifiers like hashed emails or MAIDs—Resonate still delivers strong results using household-level matching through addresses, ZIP11 or IP.

Our waterfall matching method ensures we use the best available ID in your file, always prioritizing accuracy without discarding valuable matches.

No matter what data you have, Resonate ensures you get the strongest possible match—and insights you can trust.

Want to improve your match rates?

To optimize match performance:

• Follow our Data Preparation Best Practices
• Submit as many qualifying identifiers as possible (HEMs, MAIDs, Postal Address, ZIP11)
• Format your files correctly using our File Formatting Guidelines
• Use our hashing script to standardize inputs before submission

Still have questions?

We’re happy to walk you through your match results and unlock the full value of your first-party data. Contact your client success manager or reach out to resonatesupport@resonate.com.