What’s new in 2.3.3 (September 29, 2025)

These are the changes in pandas 2.3.3. See Release notes for a full changelog including other versions of pandas.

Pandas 2.3.3 is now compatible with Python 3.14

Pandas 2.3.3 is the first version of pandas that is generally compatible with the upcoming Python 3.14, and both wheels for free-threaded and normal Python 3.14 will be uploaded for this release.

As usual please report any bugs discovered to our issue tracker

Improvements and fixes for the StringDtype

Most changes in this release are related to StringDtype which will become the default string dtype in pandas 3.0. See Upcoming changes in pandas 3.0 for more details.

Improvements

• Update DataFrame.select_dtypes() to keep selecting str columns when specifying include=["object"] for backwards compatibility. In a future release, this will be deprecated and code for pandas 3+ should be updated to do include=["str"] (GH 61916)

• Support the / operation between a pathlib.Path object and a StringDtype Series, similarly as it works for object-dtype Series (GH 61940)

Bug fixes

• Fix bug in Series.str.replace() using named capture groups (e.g., \g<name>) with the Arrow-backed dtype would raise an error (GH 57636)

• Fix regression in Series.str.contains(), match() and fullmatch() with a compiled regex and custom flags (GH 62240)

• Fix Series.str.match() and fullmatch() not matching patterns with groups correctly for the Arrow-backed string dtype (GH 61072)

• Fix bug in groupby() with sum() and unobserved categories resulting in 0 instead of the empty string "" (GH 61909)

• Fix Series.str.isdigit() to correctly recognize unicode superscript characters as digits for StringDtype backed by PyArrow (GH 61466)

• Fix comparing a StringDtype Series with mixed objects raising an error (GH 60228)

• Fix error being raised when using a numpy ufunc with a Python-backed string array (GH 40800)

Other changes

• The deprecation of using Series.resample() and DataFrame.resample() with a PeriodIndex (and the ‘convention’ keyword) has been undone. Resampling with a PeriodIndex is supported again, but a subset of methods that return incorrect results will raise an error in pandas 3.0 (GH 57033)

Other bug fixes

• Fix memory leak in DataFrame.to_json() with datetime columns (GH 62204)

• Fixed regression in DataFrame.from_records() not initializing subclasses properly (GH 57008)

• The DataFrame.iloc() now works correctly with copy_on_write option when assigning values after subsetting the columns of a homogeneous DataFrame (GH 60309)

Contributors

A total of 15 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.

• ChiLin Chiu

• Evgenii Mosikhin +

• Ian Hunt-Isaak +

• Joris Van den Bossche

• Laurie O +

• Lumberbot (aka Jack)

• Matthew Roeschke

• Nathan Goldbaum

• Patrick Hoefler

• Richard Shadrach

• Scott Talbert

• jbrockmendel

• pandas Development Team

• ptth222 +

• Álvaro Kothe +