diff --git a/examples/tv-casting-app/tv-casting-common/core/CastingPlayer.h b/examples/tv-casting-app/tv-casting-common/core/CastingPlayer.h
index 3f33b69e526c0e..bfa048e8984651 100644
--- a/examples/tv-casting-app/tv-casting-common/core/CastingPlayer.h
+++ b/examples/tv-casting-app/tv-casting-common/core/CastingPlayer.h
@@ -40,7 +40,8 @@ using ConnectCallback    = std::function<void(ConnectionError)>;
 using DisconnectCallback = std::function<void(void)>;
 
 const int kPortMaxLength = 5; // port is uint16_t
-const int kIdMaxLength   = chip::Dnssd::kHostNameMaxLength + kPortMaxLength;
+// +1 for the : between the hostname and the port.
+const int kIdMaxLength   = chip::Dnssd::kHostNameMaxLength + kPortMaxLength + 1;
 
 class CastingPlayerAttributes
 {