Does Microsoft Excel Support CSV Files with UTF-8 Encoding?

February 9, 2026 · File Format Compatibility

Introduction

CSV (Comma-Separated Values) is one of the most common data exchange formats. When CSV files contain international characters — accented letters, Chinese/Japanese/Korean text, or emoji — encoding matters. Excel’s handling of UTF-8 CSV has been a long-standing pain point.

Key Takeaways

• Excel can read UTF-8 CSV but doesn’t always detect the encoding automatically.
• Double-clicking a CSV often produces garbled characters (mojibake) if the file lacks a BOM.
• Adding a UTF-8 BOM to the file makes Excel detect encoding correctly on double-click.
• File > Open import wizard lets you manually specify UTF-8 encoding.
• Excel 365 / Excel 2021+ have improved UTF-8 auto-detection compared to older versions.

The Problem

When you double-click a .csv file to open it in Excel:

1. Excel uses the system’s default encoding (typically Windows-1252 on English systems).
2. UTF-8 multi-byte characters are misinterpreted.
3. You see garbled text like é instead of é, or 中文 instead of 中文.

This happens because standard UTF-8 CSV files don’t include a byte order mark, and Excel doesn’t assume UTF-8.

Solutions

Solution 1: Add a UTF-8 BOM

The simplest fix for files you control is to save them with a UTF-8 BOM:

• In Notepad (Windows 11): Save As > Encoding > “UTF-8 with BOM”
• In Python: open('file.csv', 'w', encoding='utf-8-sig')
• In Node.js: Prepend '\uFEFF' before writing the file.

Excel will then auto-detect UTF-8 when you double-click the file.

Solution 2: Use the Import Wizard

1. Open Excel (don’t double-click the CSV).
2. Go to Data > From Text/CSV (or File > Open in older versions).
3. Select the CSV file.
4. In the preview, change File Origin to 65001: Unicode (UTF-8).
5. Click Load.

Solution 3: Save as .xlsx

If you’re distributing data, save as .xlsx instead of .csv. Excel’s native format handles Unicode correctly without encoding issues.

Version Comparison

Conclusion

Excel does support UTF-8 CSV files, but the experience depends on your Excel version and how you open the file. The most reliable approach is to add a UTF-8 BOM to your CSV files or use the import wizard. If you’re using Excel 365, auto-detection has improved significantly, though a BOM still provides the most consistent results across all versions.