A CSV import is a data-interpretation step, not just a file-opening operation. Check the destination, separator, character encoding, and field types before replacing working records.
Keep the original and choose a safe destination
Retain the source CSV unchanged. In Sheets, use File > Import, choose the file, and review the available import-location options. A new spreadsheet or separate sheet is safer for an initial reconciliation than replacing a live dataset.
Record the source’s expected row count and column names. Confirm which file version you selected, especially when downloads have similar names.
Inspect separators and interpretation
Choose the separator matching the actual file: a CSV-style export may use commas, semicolons, or another convention. Inspect sample fields that contain the delimiter inside quoted text.
Check accented characters and other non-ASCII text for encoding problems. Inspect automatic number, date, and formula conversion options where offered. Preserve identifiers as text when leading zeros or long digit strings matter.
Reconcile before using the data
Compare headers, record counts, known amounts, dates, and representative IDs. Test a row with quoted punctuation, an empty field, and a multiline value if the source permits them.
Do not fix garbled text by manually rewriting a few visible names while leaving the import boundary unresolved. Obtain a correctly encoded source or an approved conversion. Keep suspect values separate, and inspect formula-like external strings before allowing them to execute as formulas. Only replace the operational range after the imported structure and key fields match the source; opening without an error does not establish that the data was preserved.
References
- Learn how to optimize your data ingestion
- Format numbers in a spreadsheet
- Set a spreadsheet’s location & calculation settings
Reviewed against the linked official product guidance on November 3, 2026. Features, limits, screen labels, and access can vary by account, platform, region, and organization policy.