diff --git a/lib/spack/spack/version.py b/lib/spack/spack/version.py
index 89fcc9aaa71..1c931ae90ac 100644
--- a/lib/spack/spack/version.py
+++ b/lib/spack/spack/version.py
@@ -226,6 +226,9 @@ def __repr__(self):
     def __str__(self):
         return self.string
 
+    def __format__(self, format_spec):
+        return self.string.format(format_spec)
+
     @property
     def concrete(self):
         return self