diff --git a/CHANGELOG b/CHANGELOG
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,3 +1,7 @@
+2024-07-07
+        * Version bump (3.20). (#522)
+        * What4 upper-bound dependency version bump. (#514)
+
 2024-05-07
         * Version bump (3.19.1). (#512)
         * Fix handling of unsatisfiable properties with Kind2. (#495)
diff --git a/copilot-theorem.cabal b/copilot-theorem.cabal
--- a/copilot-theorem.cabal
+++ b/copilot-theorem.cabal
@@ -14,7 +14,7 @@
   <https://copilot-language.github.io>.
 
 
-version                   : 3.19.1
+version                   : 3.20
 license                   : BSD3
 license-file              : LICENSE
 maintainer                : Ivan Perez <ivan.perezdominguez@nasa.gov>
@@ -61,10 +61,10 @@
                           , random                >= 1.1 && < 1.3
                           , transformers          >= 0.5 && < 0.7
                           , xml                   >= 1.3 && < 1.4
-                          , what4                 >= 1.3 && < 1.6
+                          , what4                 >= 1.3 && < 1.7
 
-                          , copilot-core          >= 3.19.1 && < 3.20
-                          , copilot-prettyprinter >= 3.19.1 && < 3.20
+                          , copilot-core          >= 3.20 && < 3.21
+                          , copilot-prettyprinter >= 3.20 && < 3.21
 
   exposed-modules         : Copilot.Theorem
                           , Copilot.Theorem.Prove