diff --git a/Language/Haskell/TH/ExpandSyns.hs b/Language/Haskell/TH/ExpandSyns.hs
--- a/Language/Haskell/TH/ExpandSyns.hs
+++ b/Language/Haskell/TH/ExpandSyns.hs
@@ -163,6 +163,10 @@
     go (DefaultD {}) = return ()
 #endif
 
+#if MIN_VERSION_template_haskell(2,20,0)
+    go (TypeDataD {}) = return ()
+#endif
+
 warnTypeFamiliesInType :: Type -> Q ()
 warnTypeFamiliesInType = go
   where
diff --git a/changelog.markdown b/changelog.markdown
--- a/changelog.markdown
+++ b/changelog.markdown
@@ -1,3 +1,8 @@
+## 0.4.11.0 [2023.01.31]
+
+* Support `TypeDataD` when building with `template-haskell-2.20.0.0` (GHC 9.6)
+  or later.
+
 ## 0.4.10.0 [2022.07.23]
 
 * Support `DefaultD`, `PromotedInfixT`, and `PromotedUInfixT` when building
diff --git a/th-expand-syns.cabal b/th-expand-syns.cabal
--- a/th-expand-syns.cabal
+++ b/th-expand-syns.cabal
@@ -1,5 +1,5 @@
 name:                th-expand-syns
-version:             0.4.10.0
+version:             0.4.11.0
 synopsis:            Expands type synonyms in Template Haskell ASTs
 description:         Expands type synonyms in Template Haskell ASTs.
                      .
@@ -41,7 +41,7 @@
                        , containers
                        , syb
                        , th-abstraction   >= 0.4.3 && < 0.5
-                       , template-haskell >= 2.5   && < 2.20
+                       , template-haskell >= 2.5   && < 2.21
     ghc-options:         -Wall
     exposed-modules:     Language.Haskell.TH.ExpandSyns
     other-modules:       Language.Haskell.TH.ExpandSyns.SemigroupCompat