diff --git a/pyproject.toml b/pyproject.toml
index fc78191..8420d69 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,7 +17,7 @@ repository = "https://github.com/cemsbv/pygef"
 
 [project.optional-dependencies]
 plot = ["matplotlib>=3.6,<4"]
-test = ["coveralls>=3,<4", "pytest>=9,<10"]
+test = ["coveralls>=4,<5", "pytest>=9,<10"]
 docs = [
   "Sphinx",
   "sphinx-autodoc-typehints",
diff --git a/requirements.txt b/requirements.txt
index 241a9f8..3f1a55a 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -39,7 +39,7 @@ contourpy==1.3.3
     # via matplotlib
 coverage==6.5.0
     # via coveralls
-coveralls==3.3.1
+coveralls==4.1.0
     # via pygef (pyproject.toml)
 cycler==0.12.1
     # via matplotlib