diff --git a/changelogs/fragments/ansible-connection_decode.yml b/changelogs/fragments/ansible-connection_decode.yml
new file mode 100644
index 00000000000..7e13dc98265
--- /dev/null
+++ b/changelogs/fragments/ansible-connection_decode.yml
@@ -0,0 +1,3 @@
+bugfixes:
+  - ansible-connection - decrypt vaulted parameters before sending over the socket, as
+    vault secrets are not available on the other side.
diff --git a/lib/ansible/module_utils/connection.py b/lib/ansible/module_utils/connection.py
index fd0b134087c..1396c1c1510 100644
--- a/lib/ansible/module_utils/connection.py
+++ b/lib/ansible/module_utils/connection.py
@@ -144,7 +144,7 @@ class Connection(object):
             )
 
         try:
-            data = json.dumps(req, cls=AnsibleJSONEncoder)
+            data = json.dumps(req, cls=AnsibleJSONEncoder, vault_to_text=True)
         except TypeError as exc:
             raise ConnectionError(
                 "Failed to encode some variables as JSON for communication with ansible-connection. "