Does Clay create duplicates in Attio?

It can, depending on which action you use. Clay's Create record action writes a new record every time, so pushing the same list twice creates duplicates. Its Upsert record action matches on a unique attribute such as email address or domain and updates the existing record instead. Clay's own documentation recommends upsert when you are not certain whether the record already exists.

Can Clay clean up duplicates that are already in Attio?

No. Clay writes records into Attio and enriches them; it does not scan an Attio object for duplicate groups, and it cannot merge two Attio records into one. Duplicates that arrived from a CSV import, a form, email sync or a person typing are outside what an enrichment tool acts on.

Should you use Clay and Deduptio together?

That is the normal arrangement. Clay is how new, enriched records get into Attio; using its upsert action keeps it from adding to the pile. Deduptio clears what is already there and catches the near-matches that exact-attribute upsert misses, such as a person whose email changed or a company operating on a second domain.

Why does upsert still leave duplicates?

Because upsert is exact matching on one attribute. If the incoming record has no email, uses a different email than the record already in Attio, or belongs to a company that exists under another domain, there is nothing for the match to hit — so Attio creates a new record, correctly, on the information it was given.

Deduptio vs Clay

Last checked September 1, 2026 · Deduptio is our product. Every claim about another tool comes from its public site or documentation and is linked in place — tell us if something is out of date.

Clay is a data enrichment and outbound tool that writes into Attio. Deduptio removes duplicate records from Attio. They meet at exactly one point: how carefully Clay writes determines how much Deduptio finds later.

The short version:use Clay's upsert action rather than create, and Clay stops being a source of duplicates. That is the whole overlap. It does nothing about the duplicates already in your workspace, and enrichment is exactly the workflow that exposes them — the moment you push a list of 2,000 enriched contacts, every near-match in Attio becomes a decision.

Side by side

Job	Clay	Deduptio
Enrich and source new records	Yes The product	No Not what it does
Avoid creating a duplicate on write	Yes Upsert on a unique attribute	No Runs after the fact
Find duplicates already in Attio	No No scan of an Attio object	Yes Paged scan, exact or fuzzy, any object
Match beyond one exact attribute	No Upsert matches one unique attribute	Yes Multi-key rules with AND/OR and fuzzy comparison
Merge two Attio records into one	No Not supported	Yes Attio's native merge, single or bulk
Review queue before anything is written	Partial Table review of rows, not of Attio duplicate groups	Yes Side-by-side groups with the match reason
Undo	No Records written are written	Yes 24-hour rollback from an automatic snapshot
Cost shape	Credit-based, scales with enrichment volume	Flat: free plan, or $59/month

Get the Clay side right first

Clay offers three ways to write to Attio, and the choice is the entire duplicate story:

Create record writes a new record unconditionally. Run the same table twice and you have two of everything.
Update record needs a record id, so it can only touch records you have already resolved.
Upsert recordmatches on a unique attribute — email address for people, domain for companies — and updates the record holding that value, or creates one if none does. Clay's documentation recommends this when you are unsure, and that is the right default.

Get that one dropdown right and Clay is not the reason your workspace has duplicates. It is the cheapest fix in this entire comparison.

Why upsert still leaves work

Upsert is exact matching on a single attribute, and enrichment data is precisely where exact matching runs out:

The email is new. The person changed jobs, so the enriched record carries their current work address while Attio holds the old one. Nothing matches, and a second person record is created — correctly, on the evidence available.
There is no email. A company-level or role-level row has nothing to match on, so it always creates.
The company has another domain.A rebrand, an acquisition, a regional domain, or an enrichment provider returning the parent company's domain rather than the one already in Attio.
The duplicate is in Attio, not in Clay. Two person records already exist for the same human; upsert picks one and enriches it, leaving the other stale. Now the duplicates disagree, which is worse than duplicates that agree.

That last case is the one worth watching. Enrichment applied to half of a duplicate pair produces two records with conflicting titles, companies and seniority — and whichever one your sequence picks is a coin flip. See finding duplicate people in Attio for rules that match on more than the current email.

The order that works

Dedupe before you enrich. Cleaning first means every enrichment credit lands on a record you will keep, and you are not paying to enrich both halves of a pair.
Switch every Clay write to upsert, with a matching attribute that genuinely identifies the record.
Scan again after a large push. New records from a fresh source are exactly when near-matches appear; a scheduled weekly scan catches them without anyone remembering to look.

Clean the object before the next enrichment run

A read-only scan tells you how many duplicate groups a Clay push would be landing on top of. Nothing is written to Attio until you approve a merge.

Start a free Attio duplicate scan

Deduptio vs Zapier or Make — the same prevention-versus-cleanup line through an automation platform.
Attio duplicate detection with the API — what assert, search and merge actually give you.
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