diff --git a/charts/matrix-synapse/templates/well-known-config.yaml b/charts/matrix-synapse/templates/well-known-config.yaml
index 8b9cef1..bd2274e 100644
--- a/charts/matrix-synapse/templates/well-known-config.yaml
+++ b/charts/matrix-synapse/templates/well-known-config.yaml
@@ -11,6 +11,9 @@ metadata:
 data:
   lighttpd.conf: |
     server.port = 8080
+    {{ if .Values.wellknown.useIpv6}}
+    server.use-ipv6 = "enable"
+    {{ end }}
     server.modules = (
       "mod_rewrite",
       "mod_status",
diff --git a/charts/matrix-synapse/values.yaml b/charts/matrix-synapse/values.yaml
index d98f738..2bbd971 100644
--- a/charts/matrix-synapse/values.yaml
+++ b/charts/matrix-synapse/values.yaml
@@ -510,6 +510,10 @@ wellknown:
   enabled: false
   replicaCount: 1
 
+  # Lighttpd does not bind on IPv6 by default, although this is required in
+  # Ipv6-only clusters.
+  useIpv6: false
+
   ## The host and port combo to serve on .well-known/matrix/server.
   ##
   server: {}