diff --git a/.ci_support/environment-mpich.yml b/.ci_support/environment-mpich.yml
index 7d29835..d6eab39 100644
--- a/.ci_support/environment-mpich.yml
+++ b/.ci_support/environment-mpich.yml
@@ -5,7 +5,7 @@ dependencies:
 - lammps =2024.06.27
 - mpich
 - numpy =1.26.4
-- mpi4py =3.1.6
+- mpi4py =4.0.0
 - executorlib =0.0.1
 - ase =3.23.0
 - scipy =1.14.0
diff --git a/.ci_support/environment-openmpi.yml b/.ci_support/environment-openmpi.yml
index 236cbf8..fb89f07 100644
--- a/.ci_support/environment-openmpi.yml
+++ b/.ci_support/environment-openmpi.yml
@@ -5,7 +5,7 @@ dependencies:
 - lammps =2024.06.27
 - openmpi
 - numpy =1.26.4
-- mpi4py =3.1.6
+- mpi4py =4.0.0
 - executorlib =0.0.1
 - ase =3.23.0
 - scipy =1.14.0
diff --git a/binder/environment.yml b/binder/environment.yml
index 5d8b803..b8193ed 100644
--- a/binder/environment.yml
+++ b/binder/environment.yml
@@ -4,7 +4,7 @@ dependencies:
 - openmpi
 - numpy =1.26.4
 - lammps =2024.06.27
-- mpi4py =3.1.6
+- mpi4py =4.0.0
 - executorlib =0.0.1
 - ase =3.23.0
 - scipy =1.14.0
diff --git a/pyproject.toml b/pyproject.toml
index 3d6c03d..836a7e7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -24,7 +24,7 @@ classifiers = [
     "Programming Language :: Python :: 3.12",
 ]
 dependencies = [
-    "mpi4py==3.1.6",
+    "mpi4py==4.0.0",
     "executorlib==0.0.1",
     "numpy==1.26.4",
 ]