diff --git a/binaries/data/mods/public/gui/lobby/AccountSettingsPage/AccountSettingsPage.js b/binaries/data/mods/public/gui/lobby/AccountSettingsPage/AccountSettingsPage.js
index 08aefb87bc..30e149bb6f 100644
--- a/binaries/data/mods/public/gui/lobby/AccountSettingsPage/AccountSettingsPage.js
+++ b/binaries/data/mods/public/gui/lobby/AccountSettingsPage/AccountSettingsPage.js
@@ -98,14 +98,6 @@ var AccountSettingsPage = {
 		if (Engine.GetGUIObjectByName("as_PasswordInputConfirm").caption !== newPass)
 			throw new SetPasswordError(translate("Passwords do not match"));
 
-		let usn = Engine.LobbyGetJID();
-		let atIndex = usn.indexOf("@");
-		if (atIndex == -1)
-		{
-			// Probably can't happen too easily, so error out.
-			error("Invalid JID");
-			throw new SetPasswordError(translate("Invalid JID, cannot change password."));
-		}
-		return Engine.EncryptPassword(newPass, usn.substring(0, atIndex).toLowerCase());
+		return Engine.EncryptPassword(newPass, Engine.LobbyGetUsername());
 	}
 };
diff --git a/source/lobby/IXmppClient.h b/source/lobby/IXmppClient.h
index 491da0c60f..4aced9ee6d 100644
--- a/source/lobby/IXmppClient.h
+++ b/source/lobby/IXmppClient.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -43,6 +43,7 @@ public:
 	virtual void SetNick(const std::string& nick) = 0;
 	virtual std::string GetNick() const = 0;
 	virtual std::string GetJID() const = 0;
+	virtual std::string GetUsername() const = 0;
 	virtual void ChangePassword(const std::string& newPassword) = 0;
 	virtual void kick(const std::string& nick, const std::string& reason) = 0;
 	virtual void ban(const std::string& nick, const std::string& reason) = 0;
diff --git a/source/lobby/XmppClient.cpp b/source/lobby/XmppClient.cpp
index 364c09a26e..2d9170c1b1 100644
--- a/source/lobby/XmppClient.cpp
+++ b/source/lobby/XmppClient.cpp
@@ -1185,9 +1185,9 @@ const std::wstring& XmppClient::GetSubject()
 }
 
 /**
- * Request nick change, real change via mucRoomHandler.
+ * Request MUC nick change, real change via mucRoomHandler.
  *
- * @param nick Desired nickname
+ * @param nick Desired MUC nickname
  */
 void XmppClient::SetNick(const std::string& nick)
 {
@@ -1195,7 +1195,7 @@ void XmppClient::SetNick(const std::string& nick)
 }
 
 /**
- * Get current nickname.
+ * Get current MUC nickname.
  */
 std::string XmppClient::GetNick() const
 {
@@ -1207,6 +1207,17 @@ std::string XmppClient::GetJID() const
 	return m_client->jid().full();
 }
 
+
+/**
+ * Get the XMPP username.
+ *
+ * @return current XMPP username
+ */
+std::string XmppClient::GetUsername() const
+{
+	return m_username;
+}
+
 /**
  * Change password for authenticated user.
  *
@@ -1214,7 +1225,7 @@ std::string XmppClient::GetJID() const
  */
 void XmppClient::ChangePassword(const std::string& newPassword)
 {
-	m_registration->changePassword(m_username, newPassword);
+	m_registration->changePassword(m_client->jid().username(), newPassword);
 }
 
 /**
diff --git a/source/lobby/XmppClient.h b/source/lobby/XmppClient.h
index 634c324c58..28730619f4 100644
--- a/source/lobby/XmppClient.h
+++ b/source/lobby/XmppClient.h
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -88,6 +88,7 @@ public:
 	void SetNick(const std::string& nick) override;
 	std::string GetNick() const override;
 	std::string GetJID() const override;
+	std::string GetUsername() const override;
 	void ChangePassword(const std::string& newPassword) override;
 	void kick(const std::string& nick, const std::string& reason) override;
 	void ban(const std::string& nick, const std::string& reason) override;
diff --git a/source/lobby/scripting/JSInterface_Lobby.cpp b/source/lobby/scripting/JSInterface_Lobby.cpp
index 33765c3028..06076984f4 100644
--- a/source/lobby/scripting/JSInterface_Lobby.cpp
+++ b/source/lobby/scripting/JSInterface_Lobby.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2024 Wildfire Games.
+/* Copyright (C) 2025 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -218,6 +218,7 @@ void RegisterScriptFunctions(const ScriptRequest& rq)
 	REGISTER_XMPP(SetNick, "LobbySetNick");
 	REGISTER_XMPP(GetNick, "LobbyGetNick");
 	REGISTER_XMPP(GetJID, "LobbyGetJID");
+	REGISTER_XMPP(GetUsername, "LobbyGetUsername");
 	REGISTER_XMPP(ChangePassword, "LobbyChangePassword");
 	REGISTER_XMPP(kick, "LobbyKick");
 	REGISTER_XMPP(ban, "LobbyBan");