diff --git a/doc/lightningd-config.5.md b/doc/lightningd-config.5.md
index 92fc7e63f..6049178b5 100644
--- a/doc/lightningd-config.5.md
+++ b/doc/lightningd-config.5.md
@@ -391,7 +391,9 @@ Set an IP address (v4 or v6) or automatic Tor address to listen on and
 
 An empty 'IPADDRESS' is a special value meaning bind to IPv4 and/or
 IPv6 on all interfaces, '0.0.0.0' means bind to all IPv4
-interfaces, '::' means 'bind to all IPv6 interfaces'.
+interfaces, '::' means 'bind to all IPv6 interfaces' (if you want to
+specify an IPv6 address *and* a port, use `[]` around the IPv6
+address, like `[::]:9750`).
 If 'PORT' is not specified, the default port 9735 is used for mainnet
 (testnet: 19735, signet: 39735, regtest: 19846).
 If we can determine a public IP address from the resulting binding,