CSV is not a spreadsheet format
When you save a workbook as CSV, you lose workbook features such as formulas, formatting, multiple sheets, cell types, and some metadata. What remains is plain text. That makes CSV portable, but it also means spreadsheet software has to convert typed cells into text.
Watch identifiers with leading zeros
Postal codes, SKUs, account numbers, and product codes may look numeric but are identifiers. A spreadsheet can turn 001234 into 1234. Once the zeros are removed before export, a CSV repair tool cannot know they were supposed to exist.
Watch long numbers and scientific notation
Very long numeric identifiers can be displayed or stored in scientific notation. If the spreadsheet has already rounded or changed the value, exporting to CSV preserves the changed value, not the original identifier.
Dates are especially easy to reinterpret
Values such as 03/04/2026 can mean different dates depending on locale. A spreadsheet may also convert text-like values into date serials. Define the required destination format before export.
Use UTF-8 when the destination expects UTF-8
If the application offers multiple CSV choices, prefer an explicit UTF-8 CSV option when that is what the importer requires. Do not assume every “CSV” menu item uses the same encoding.
Confirm the delimiter after export
Regional settings can produce semicolon-delimited text. Open the exported file in a plain-text editor or run the Delimiter Checker before uploading to a system that expects commas.
Values beginning with formula characters need review
Cells beginning with =, +, -, or @ can be interpreted as formulas by spreadsheet applications. Whether that is dangerous or intentional depends on the workflow, so a safe CSV tool should flag suspicious cells rather than rewrite them without permission.
Recommended export workflow
- Duplicate the workbook or worksheet.
- Convert identifier columns to text before editing them.
- Verify dates and long numbers.
- Export only the sheet you intend to import.
- Choose UTF-8 if the destination requires it.
- Run a CSV structural check.
- Test a small import.
- Only then run the full production import.