diff --git a/code/modules/asset_cache/asset_list.dm b/code/modules/asset_cache/asset_list.dm
index 221febbe14..3f9e8c3fcc 100644
--- a/code/modules/asset_cache/asset_list.dm
+++ b/code/modules/asset_cache/asset_list.dm
@@ -11,6 +11,7 @@ GLOBAL_LIST_EMPTY(asset_datums)
 
 /datum/asset
 	var/_abstract = /datum/asset
+	var/cached_url_mappings
 
 /datum/asset/New()
 	GLOB.asset_datums[type] = src
@@ -19,6 +20,13 @@ GLOBAL_LIST_EMPTY(asset_datums)
 /datum/asset/proc/get_url_mappings()
 	return list()
 
+/// Returns a cached tgui message of URL mappings
+/datum/asset/proc/get_serialized_url_mappings()
+	if (isnull(cached_url_mappings))
+		cached_url_mappings = TGUI_CREATE_MESSAGE("asset/mappings", get_url_mappings())
+
+	return cached_url_mappings
+
 /datum/asset/proc/register()
 	return
 
diff --git a/code/modules/tgui/tgui_window.dm b/code/modules/tgui/tgui_window.dm
index b4a509c6da..08f0ad704b 100644
--- a/code/modules/tgui/tgui_window.dm
+++ b/code/modules/tgui/tgui_window.dm
@@ -251,7 +251,7 @@
 	if(istype(asset, /datum/asset/spritesheet))
 		var/datum/asset/spritesheet/spritesheet = asset
 		send_message("asset/stylesheet", spritesheet.css_filename())
-	send_message("asset/mappings", asset.get_url_mappings())
+	send_raw_message(asset.get_serialized_url_mappings())
 
 /**
  * private