diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b8f5cbe8..b1fed832 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.9", "3.10", "3.11"]
+        python-version: ["3.10", "3.11"]
 
     steps:
     - uses: actions/checkout@v4
diff --git a/README.md b/README.md
index 3b6558aa..014010dd 100644
--- a/README.md
+++ b/README.md
@@ -132,7 +132,7 @@ The following describes the typical work flow for contributing to the pysiaf pro
 11. Delete your local copy of your branch.
 
 ### Installation  
-This package is supported in python 3.8 and 3.9
+This package is supported in python 3.10+
 
 `pip install pysiaf`
 
diff --git a/pyproject.toml b/pyproject.toml
index 4d90904f..a377a931 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,6 +24,7 @@ dependencies = [
 dynamic = [
     "version",
 ]
+requires-python = ">=3.10"
 
 [project.readme]
 file = "README.md"
@@ -39,7 +40,7 @@ repository = "https://github.com/spacetelescope/pysiaf"
 
 [project.optional-dependencies]
 test = [
-    'pytest',
+    "pytest",
 ]
 docs = [
     "stsci-rtd-theme",