diff --git a/tagged.cabal b/tagged.cabal
index ccde4af..acfb4fd 100644
--- a/tagged.cabal
+++ b/tagged.cabal
@@ -81,7 +81,7 @@ library
     build-depends: deepseq >= 1.1 && < 1.5
 
   if flag(transformers)
-    build-depends: transformers        >= 0.2 && < 0.6
+    build-depends: transformers        >= 0.2 && < 0.7
 
     -- Ensure Data.Functor.Classes is always available
     if impl(ghc >= 7.10) || impl(ghcjs)