diff --git a/pyproject.toml b/pyproject.toml
index e3a292e2f..4c456da5d 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -39,6 +39,7 @@ dependencies = [
     "psygnal>=0.5.0",
     "qtpy>=1.7.0",
     "superqt>=0.5.0",
+    "pint",
     "typing_extensions",
 ]
 
diff --git a/setup.py b/setup.py
index 3f6e2cd46..55f6b797d 100644
--- a/setup.py
+++ b/setup.py
@@ -25,6 +25,7 @@
         "psygnal>=0.5.0",
         "qtpy>=1.7.0",
         "superqt>=0.5.0",
+        "pint",
         "typing_extensions",
     ],
 )