Google Ads Offline Conversion CSV Errors
Offline conversion import errors are often caused by CSV-level problems that can be caught before upload. Use this guide to decide which rows to fix before opening Google Ads preview.
Last updated: June 6, 2026. Re-check the official Google Ads documentation before changing production import workflows.
Common CSV-level errors and fixes
| Issue | Why it matters | Next action |
|---|---|---|
| Missing or duplicate headers | Headers such as Conversion Name, Conversion Time, click ID, value, currency, consent, or user-data fields cannot be mapped reliably. | Fix blank, duplicated, or renamed headers before upload. |
| Invalid conversion time | Date-only, future, timezone-less, unparseable, or old rows can fail preview or create attribution confusion. | Use a supported timestamp format and a clear row-level timezone or Parameters:TimeZone row. |
| Missing or invalid identifiers | Rows without a valid click ID, valid email, valid phone, or usable address-style user data cannot be matched locally. | Choose the correct workflow and fix invalid identifiers before preview. |
| Plain or invalid user data | Scheduled/pre-hashed workflows should not contain plain email, phone, first name, last name, or street address values. | Normalize and SHA-256 hash where your workflow requires pre-hashed user data. |
| Consent value problems | Unexpected Ad User Data or Ad Personalization values may not match your workflow expectations. | Review consent mapping before previewing the file in Google Ads. |
| Value, currency, and duplicate risks | Invalid numeric values, non-ISO currency codes, duplicate conversion keys, and repeated Order IDs can create upload or reporting problems. | Fix the report rows, then preview the corrected file in Google Ads. |
Why old rows are flagged
The checker uses different age windows by workflow. Click-ID upload rows are reviewed against a 90-day offline conversion window, while user-data / enhanced-conversion preflight rows are reviewed against a 63-day window. Treat these as local review signals, then confirm final eligibility in Google Ads.
What this local checker cannot verify
The checker reads a CSV in your browser and reports file-level risks. It does not connect to Google Ads, Data Manager, Google Ads API, your CRM, or your account. It cannot confirm conversion action ownership, click ownership, account permissions, customer data terms, Data Manager schema rules, template compatibility for every file format, import preview status, or final attribution. Always preview and validate the corrected file in the official Google Ads workflow.
Official sources used
These links support the page boundary and the local checks described here. They are not copied into the checker as a complete Google Ads validator, and the checker should not be described as official Google guidance.
- Google Ads Help: Import conversions from ad clicks using files
Used for file-level timezone parameters, supported conversion time formats, file import boundaries, and scheduled upload hashing notes.
- Google Ads Help: Guidelines for importing offline conversions
Used for upload timing windows, old conversion review signals, and final Google Ads validation boundaries.
- Google Ads Help: About enhanced conversions for leads
Used for the enhanced conversions for leads and Data Manager boundary.
- Google Ads API: Manage offline conversions
Used for API-style offline conversion and hashed user-provided data context.
Check your CSV before upload
Use the free browser-local checker to find missing fields, invalid times, suspicious identifiers, user data issues, consent values, currency problems, and duplicate rows before import.
Open the checker