Common Google Ads Offline Conversion Import Errors
Fix mismatched conversion names, missing match identifiers, bad timestamps, duplicate events, currency problems, and legacy workflow confusion before import.
An offline conversion CSV can be syntactically valid and still fail in Google Ads. The most useful checks happen before upload: confirm the workflow, identifier fields, conversion action, timestamp, and optional value fields all mean what Google expects.
Conversion name does not match
Conversion Name identifies the Google Ads conversion action. A CRM stage such as Closed Won is only correct if that is the exact action name configured in the account. Map the right source column and normalize the source values before export if the names differ.
Match identifier is missing
Legacy imports need the GCLID that came from the original ad click. Enhanced lead workflows use first-party identifiers such as email or phone and benefit from GCLID when available. A row with no identifier cannot be attributed.
Conversion time is ambiguous
Keep the event time from the actual offline conversion and include its timezone. Avoid silently converting a local CRM timestamp into UTC unless you know the source timezone.
Value and currency disagree
If you include a conversion value, map the matching currency field as well. Use a normal three-letter currency code such as EUR or USD; do not put a currency symbol into the currency column.
Duplicate event
Repeated identifiers combined with the same conversion action and timestamp can be treated as duplicate data. An order ID is useful when your workflow has a stable transaction or deal identifier.
Wrong workflow
The most important 2026 error is conceptual: a new Enhanced Conversions for Leads setup should follow the current Google Ads Data Manager guidance, while the old file-upload article describes a legacy path. The Nablyx mapper makes that distinction before you choose columns.
Map the file locally up to 200 MB, then use Google's import diagnostics for any account-specific rejection.
Map the CSV before retryingSee the transformation
Awkward source headers become import-ready columns.
Rename the columns you need while keeping every value under the correct header.
cust_idcustomer_idgiven_namefirst_namemailemail✓ Values stay with the right column
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