diff --git a/src/openrct2-ui/windows/AssetPacks.cpp b/src/openrct2-ui/windows/AssetPacks.cpp
index c1294304d0..e0a577e8b9 100644
--- a/src/openrct2-ui/windows/AssetPacks.cpp
+++ b/src/openrct2-ui/windows/AssetPacks.cpp
@@ -110,9 +110,9 @@ public:
         if (index < 0 || static_cast<size_t>(index) >= GetNumAssetPacks())
             return;
 
-        if (_selectedIndex != index)
+        if (_selectedIndex != static_cast<size_t>(index))
         {
-            _selectedIndex = index;
+            _selectedIndex = static_cast<size_t>(index);
             Invalidate();
         }
     }
@@ -123,9 +123,9 @@ public:
         if (index < 0 || static_cast<size_t>(index) >= GetNumAssetPacks())
             return;
 
-        if (_highlightedIndex != index)
+        if (_highlightedIndex != static_cast<size_t>(index))
         {
-            _highlightedIndex = index;
+            _highlightedIndex = static_cast<size_t>(index);
             Invalidate();
         }
     }