diff --git a/requirements_dev.txt b/requirements_dev.txt
index 0dfd8babd..818e30978 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -7,8 +7,7 @@ bump2version>=0.5.11
 
 # glotaran setup dependencies
 asteval==0.9.21
-numpy==1.19.4; sys_platform != "win32"
-numpy==1.19.3; sys_platform == "win32"
+numpy==1.19.5
 scipy==1.6.0
 click==7.1.2
 numba==0.52.0
diff --git a/setup.py b/setup.py
index fe04a7b4b..b3fb821a8 100644
--- a/setup.py
+++ b/setup.py
@@ -6,8 +6,7 @@
     "click>=7.0",
     "netCDF4>=1.5.3",
     "numba>=0.48",
-    'numpy>=1.17.3; sys_platform != "win32"',
-    'numpy==1.19.3; sys_platform == "win32"',
+    "numpy>=1.19.5,<1.20.0",
     "pandas>=0.25.2",
     "pyyaml>=5.2",
     "scipy>=1.3.2",