How to Read a CSV File in Python (pathlib + csv Guide)
Learn how to read a CSV file in Python with the csv module and pathlib — skip headers, map rows to dicts, write CSVs cleanly, and avoid the classic blank-row bug.
Sooner or later every Python project touches a spreadsheet export, a log dump, or a dataset — and that means learning how to read a CSV file in Python properly. The naive approach ( line.split(",") ) breaks the moment a field contains a quoted comma, and hand-rolled path code breaks the moment it runs on a different OS. This guide does it the pathlib-first way: modern paths, the csv module used correctly, binary files when you need them, and the five mistakes that bite everyone. What you'll learn Building paths the pathlib way ( pathlib vs os.path ) How to read a CSV file in Python with csv.reader How to skip the header row Converting CSV rows to dictionaries with DictReader How to write a CSV file without the blank-row bug Reading binary files in rb mode read() vs readline() vs readlines() — and when to stream Step 1 — Build paths the pathlib way Before touching any file, get paths right. pathlib treats paths as objects instead of strings you glue together, which kills an entire class of Windows-vs-Linux bugs: from pathlib import Path # __file__ is this script's location; resolve() makes it absolute. DATA_DIR = Path(__file__).resolve().parent / "data" csv_path = DATA_DIR / "sales.csv" # the / operator joins paths print(csv_path) # .../data/sales.csv (correct separators on any OS) print(csv_path.exists()) # False until we create it print(csv_path.suffix) # .csv print(csv_path.stem) # sales # One-liners for small text files — no open() needed. DATA_DIR.mkdir(exist_ok=True) (csv_path.parent / "note.txt").write_text("hello", encoding="utf-8") print((csv_path.parent / "note.txt").read_text(encoding="utf-8")) Why pathlib over os.path in 2026? os.path.join(a, b) is just string surgery — it can't tell you a suffix, list children, or read the file itself. A Path…