Decide what counts as the same customer

Write the identity rule before searching. A contact is a person, while a company is an organization, so a shared company name does not make two contacts the same person. A company can also have more than one trading name or domain. Keep those distinctions visible in the review rather than forcing every row into one customer label.

For each record type, list the strongest identifiers already available. A source-system record ID is useful when both files refer to the same system. For contacts, an exact email match is a strong clue. For companies, a matching domain can help. Names, phone numbers, and postal addresses add context, but may be shared, outdated, or formatted differently.

Compare identifiers in layers

Start with exact identifiers, then compare secondary details. Normalize harmless formatting such as letter case or spaces in a phone number, but keep the original value in the review file. Do not silently discard a difference because it may explain why the records diverged. A person who changed jobs, for example, may still have a different current organization.

HubSpot documents contact deduplication using email and company deduplication using domain values in specified workflows. It also describes record IDs and custom unique properties for matching records during imports. Those are HubSpot rules, not a universal identity standard, and its documentation notes an exception for companies created through an API. Treat every destination system's behavior as something to confirm.

Keep a queue of candidate pairs

Give each pair a stable label such as A-014 and B-009. Record the shared signal, the conflicting detail, a decision, and the reason. The example CSV includes both likely matches and lookalikes. One pair shares a fictional company domain, while another shares a familiar name but has different domains. That second pair should remain separate unless stronger evidence appears.

Use three outcomes: merge after review, keep separate, or investigate. The queue should make uncertainty explicit. A blank decision is not permission to merge, and a fuzzy name match should not be converted into a confirmed identity just to make the import file look tidy.

Resolve field conflicts before combining records

When a pair is a genuine match, decide which value should survive for each important field. Use a source that has an owner and a reason for being trusted, such as a current client-confirmed address or a system-generated record ID. Do not assume that the newest timestamp is correct, because imports and edits can change timestamps without improving the underlying information.

Preserve useful history and links where the system supports them. If a merge would erase a note, relationship, or source reference that the team needs, pause and capture that information first. For uncertain pairs, keep separate records and add a review note rather than guessing.

Prepare the import after review

Filter the queue to records with a recorded decision. Keep confirmed matches in a reviewed file, new customers in a separate file, and unresolved candidates out of the import. Compare the final row count with the original input so that removing duplicates does not accidentally remove a real person or company.

After import, check a few reviewed pairs in the destination and confirm that the intended record was updated or created. This page focuses on identity review. A separate small-sample migration test is useful when you also need to check field mappings, associations, and how the destination handles a broader data move.

Using Areinum

Give Areinum Assistant a permitted sample of candidate records and ask for a review queue showing matching identifiers and conflicts. A person decides whether each pair represents the same customer and what should be retained.

See the example

CRM duplicate review queue

All names, domains, emails, record labels, and decisions in the worked example are fictional.

CRM duplicate review queue
Pair IDRecord typeRecord ARecord BShared signalConflict to checkDecisionReason
PAIR-001CompanyNorthstar StudioNorth Star Studionorthstar.example domainDifferent display namesMerge after reviewSource owner confirmed both names refer to the same fictional company
PAIR-002ContactMira ChenMira Chenmira@cedarbay.example emailDifferent source record IDsInvestigateConfirm the source IDs before combining
PAIR-003CompanyCedar Field WorksCedar Field WorksSame company namecedarfield.example and cedarfield.co.example domainsKeep separateA matching name alone is insufficient
PAIR-004ContactJordan EllisJ. EllisSame organization onlyNo matching email or phoneInvestigateThe shared organization does not identify the same person
  1. Use one row for each candidate pair and preserve the original source values in your working copy.
  2. Replace the fictional examples with records you are authorized to review. Record evidence and a decision before merging; leave uncertain pairs out of the import.
  3. These examples are fictional and describe a review method, not a completed import or a guarantee that a CRM will merge records in this way.

Limits of this method

  • This page proposes a manual review method. The selected evidence is vendor documentation and does not establish how common duplicate-record problems are.
  • Matching rules differ by CRM, record type, and import path. Confirm the destination behavior before merging or importing real customer data.

Questions you may have

Are two records with the same name necessarily duplicates?

No. Compare stable identifiers and relationship context; two different people or businesses may share a name.

What if two possible matches contain different field values?

Keep the conflict visible and ask the person with the relevant context which value belongs in the retained record. Do not silently choose the newest value.

Should uncertain pairs be merged before import?

Keep them separate or on hold until an authorised reviewer can decide. Record the decision and the reason before the import.

Will Areinum merge the customer records for me?

The example prepares a candidate review queue. A person checks the evidence and decides what to merge or keep separate.

Sources and further reading

  • Deduplicate records in HubSpot

    HubSpot documents contact matching by email, company matching by domain in specified workflows, and use of record IDs or custom unique values for imports.

    This is provider documentation, not a universal identity rule or evidence of demand. The page notes that companies created through an API are not deduplicated by domain.

    2026-10-18

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