diff --git a/.github/workflows/basic-tests.yml b/.github/workflows/basic-tests.yml
index ab22c715793..5053ba22a9f 100644
--- a/.github/workflows/basic-tests.yml
+++ b/.github/workflows/basic-tests.yml
@@ -25,7 +25,8 @@ jobs:
       run: |
         sudo apt-get -o Acquire::Retries=3 update
         sudo apt-get -o Acquire::Retries=3 install *fftw3* mpi intel-mkl* git-lfs graphviz
-        pip install "tox<4.0.0" pip setuptools --upgrade
+        pip install "tox<4.0.0" pip --upgrade
+        pip install setuptools==71.1.0
     - name: installing auxiliary data files
       run: |
         GIT_LFS_SKIP_SMUDGE=1 git clone https://git.ligo.org/lscsoft/lalsuite-extra
diff --git a/pyproject.toml b/pyproject.toml
index 7bb76a79ec2..c2329254c4f 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools",
+requires = ["setuptools==71.1.0",
             "wheel==0.43.0",
             "cython>=0.29.21",
             "numpy>=2.0.0",
diff --git a/tox.ini b/tox.ini
index 55ed12e9d43..8f05b04551f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@ envlist = py-unittest
 indexserver =
     preinstall = https://pypi.python.org/simple
 requires=tox-conda 
-         setuptools
+         setuptools==71.1.0
 
 [base]
 deps =