diff --git a/pyproject.toml b/pyproject.toml
index 70b8522a..0523bece 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -61,7 +61,7 @@ classifiers = [
     "Programming Language :: Python :: 3",
     "Operating System :: OS Independent",
 ]
-requires-python = ">=3.10,<4.0"
+requires-python = ">=3.9,<4.0"
 
 [project.optional-dependencies]
 burr = ["burr[start]==0.22.1"]