diff --git a/README.md b/README.md
index 97f00b6ad..19e100dee 100644
--- a/README.md
+++ b/README.md
@@ -35,7 +35,7 @@ Installation
 FloPy requires **Python** 3.9-3.12 with: 
 
 ```
-boltons
+boltons >=1.0
 numpy >=1.20.3
 matplotlib >=1.4.0
 pandas >=2.0.0
diff --git a/pyproject.toml b/pyproject.toml
index 2175c2aff..fe13645e9 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -28,7 +28,7 @@ classifiers = [
 ]
 requires-python = ">=3.9,<3.13"
 dependencies = [
-    "boltons",
+    "boltons>=1.0",
     "Jinja2>=3.0",
     "numpy>=1.20.3",
     "matplotlib >=1.4.0",