diff --git a/.ci_support/environment-mpich.yml b/.ci_support/environment-mpich.yml
index 46c5719..07d6d5f 100644
--- a/.ci_support/environment-mpich.yml
+++ b/.ci_support/environment-mpich.yml
@@ -5,7 +5,7 @@ dependencies:
 - lammps =2024.08.29=*_mpi_mpich_*
 - mpich =4.2.3
 - numpy =1.26.4
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - executorlib =0.4.2
 - ase =3.24.0
 - scipy =1.15.2
diff --git a/.ci_support/environment-openmpi.yml b/.ci_support/environment-openmpi.yml
index 948a37e..92a54df 100644
--- a/.ci_support/environment-openmpi.yml
+++ b/.ci_support/environment-openmpi.yml
@@ -5,7 +5,7 @@ dependencies:
 - lammps =2024.08.29=*_mpi_openmpi_*
 - openmpi =5.0.5
 - numpy =1.26.4
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - executorlib =0.4.2
 - ase =3.24.0
 - scipy =1.15.2
diff --git a/binder/environment.yml b/binder/environment.yml
index 927bb19..0b00706 100644
--- a/binder/environment.yml
+++ b/binder/environment.yml
@@ -4,7 +4,7 @@ dependencies:
 - openmpi
 - numpy =1.26.4
 - lammps =2024.08.29
-- mpi4py =4.0.1
+- mpi4py =4.0.3
 - executorlib =0.0.4
 - ase =3.24.0
 - scipy =1.15.2
diff --git a/pyproject.toml b/pyproject.toml
index 308d5f9..cdea768 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,7 +24,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
 ]
 dependencies = [
-    "mpi4py==4.0.1",
+    "mpi4py==4.0.3",
     "executorlib==0.4.2",
     "numpy==1.26.4",
 ]