diff --git a/.ci_support/environment-docs.yml b/.ci_support/environment-docs.yml
index 720af185..66b6fff8 100644
--- a/.ci_support/environment-docs.yml
+++ b/.ci_support/environment-docs.yml
@@ -8,7 +8,7 @@ dependencies:
 - numpy
 - openmpi
 - cloudpickle =3.1.1
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - pyzmq =26.3.0
 - flux-core
 - jupyter-book =1.0.0
diff --git a/.ci_support/environment-mpich.yml b/.ci_support/environment-mpich.yml
index 1493c25a..6b3c0ae2 100644
--- a/.ci_support/environment-mpich.yml
+++ b/.ci_support/environment-mpich.yml
@@ -5,7 +5,7 @@ dependencies:
 - numpy
 - mpich
 - cloudpickle =3.1.1
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - pyzmq =26.3.0
 - h5py =3.13.0
 - networkx =3.4.2
diff --git a/.ci_support/environment-openmpi.yml b/.ci_support/environment-openmpi.yml
index 85b35b22..acd469d6 100644
--- a/.ci_support/environment-openmpi.yml
+++ b/.ci_support/environment-openmpi.yml
@@ -5,7 +5,7 @@ dependencies:
 - numpy
 - openmpi
 - cloudpickle =3.1.1
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - pyzmq =26.3.0
 - h5py =3.13.0
 - networkx =3.4.2
diff --git a/.ci_support/environment-win.yml b/.ci_support/environment-win.yml
index 3345b3f0..c05a5c63 100644
--- a/.ci_support/environment-win.yml
+++ b/.ci_support/environment-win.yml
@@ -5,7 +5,7 @@ dependencies:
 - numpy
 - msmpi
 - cloudpickle =3.1.1
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - pyzmq =26.3.0
 - h5py =3.13.0
 - networkx =3.4.2
diff --git a/binder/environment.yml b/binder/environment.yml
index 21e09830..f6b994ba 100644
--- a/binder/environment.yml
+++ b/binder/environment.yml
@@ -5,7 +5,7 @@ dependencies:
 - numpy
 - openmpi
 - cloudpickle =3.1.1
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - pyzmq =26.3.0
 - flux-core =0.59.0
 - flux-pmix =0.5.0
diff --git a/pyproject.toml b/pyproject.toml
index c72038e7..362da4bd 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -46,13 +46,13 @@ graphnotebook = [
     "networkx==3.4.2",
     "ipython==9.0.2",
 ]
-mpi = ["mpi4py==4.0.1"]
+mpi = ["mpi4py==4.0.3"]
 cluster = [
     "pysqa==0.2.4",
     "h5py==3.13.0",
 ]
 all = [
-    "mpi4py==4.0.1",
+    "mpi4py==4.0.3",
     "pysqa==0.2.4",
     "h5py==3.13.0",
     "pygraphviz==1.14",