Deduplicating Your Data

A key part of list-building is “deduplicating”, “deduping”, your data.

In other words, ensuring the same domain or email address isn’t in your list multiple times.

It’s best to run dedupes prior to paying for enrichment, to ensure you don’t essentially enrich the same lead multiple times.

Here’s how deduping works in LeadTables…

How To Dedupe In LeadTables

Note that as of March 2, 2026, the LeadTables dedupe functionality doesn’t offer a lot of control or predictability on which duplicate gets deleted.

So in other words, if you have one row with a lot of enrichment info and one row that’s only a domain, there’s a chance that when you dedupe, you’ll remove the heavily-enriched one, and keep the unenriched one.

I’d like to improve this at some point, but for now it’s just something you should be aware of before you run it.

The best way to avoid this for now is ensure when adding new leads to your table, you’re using the LeadTables “smart merge” modes to avoid ever getting duplicate leads in the first place.

Here’s where to do it:

You can also dedupe by email for contacts: