diff --git a/distribution/changelog.txt b/distribution/changelog.txt
index 6048d6f368..d86efeb505 100644
--- a/distribution/changelog.txt
+++ b/distribution/changelog.txt
@@ -11,6 +11,7 @@
 - Improved: [#21981] The map window now defaults to showing as much of the map as fits the screen.
 - Improved: [#21983] Taking a screenshot now shows a message again, closing when taking another.
 - Improved: [#22026] The options window now stays centred when window scaling is changed.
+- Improved: [#22060] [Plugin] The scroll wheel can now be used to modify spinner widget values in custom/script windows.
 - Improved: [#22084] The game now temporarily pauses while the load/save window is open.
 - Change: [#7248] Small mini-maps are now centred in the map window.
 - Change: [#20240] Heavy snow and blizzards now make guests buy and use umbrellas.
diff --git a/src/openrct2-ui/interface/Window.cpp b/src/openrct2-ui/interface/Window.cpp
index 0d583e86bb..0e14e9c306 100644
--- a/src/openrct2-ui/interface/Window.cpp
+++ b/src/openrct2-ui/interface/Window.cpp
@@ -410,101 +410,89 @@ static void WindowViewportWheelInput(WindowBase& w, int32_t wheel)
         WindowZoomOut(w, true);
 }
 
+static bool isSpinnerGroup(WindowBase& w, WidgetIndex index, WindowWidgetType buttonType)
+{
+    const auto& widgets = w.widgets;
+
+    if (widgets[index].type != WindowWidgetType::Spinner && widgets[index].type != WindowWidgetType::ImgBtn)
+        return false;
+
+    if (widgets[index + 1].type != buttonType)
+        return false;
+
+    if (widgets[index + 2].type != buttonType)
+        return false;
+
+    return true;
+}
+
+static std::optional<WidgetIndex> getSpinnerGroupWidgetIndex(WindowBase& w, WidgetIndex startIndex)
+{
+    // We only iterate 3 times as we might be at the spinner or one of its buttons.
+    for (WidgetIndex index = 0; index < 3; index++)
+    {
+        const auto reverseIndex = startIndex - index;
+        if (reverseIndex < 0)
+        {
+            break;
+        }
+
+        if (isSpinnerGroup(w, reverseIndex, WindowWidgetType::TrnBtn))
+        {
+            return reverseIndex;
+        }
+
+        if (isSpinnerGroup(w, reverseIndex, WindowWidgetType::Button))
+        {
+            return reverseIndex;
+        }
+    }
+
+    return std::nullopt;
+}
+
+// Allow mouse wheel scrolling to manipulate spinner widgets and tool sizes
 static bool WindowOtherWheelInput(WindowBase& w, WidgetIndex widgetIndex, int32_t wheel)
 {
     // HACK: Until we have a new window system that allows us to add new events like mouse wheel easily,
     //       this selective approach will have to do.
 
-    // Allow mouse wheel scrolling to increment or decrement the land tool size for various windows
-    auto widgetType = w.widgets[widgetIndex].type;
-
-    // Lower widgetIndex once or twice we got a type that matches, to allow scrolling on the increase/decrease buttons too
-    int32_t attempts = 0;
-    while (widgetType != WindowWidgetType::ImgBtn && widgetType != WindowWidgetType::Spinner && widgetIndex > 0)
-    {
-        switch (widgetType)
-        {
-            case WindowWidgetType::TrnBtn: // + and - for preview widget
-            case WindowWidgetType::Button: // + and - for spinner widget
-            {
-                if (attempts > 0)
-                {
-                    // Verify that the previous button was of the same type
-                    auto previousType = w.widgets[widgetIndex + 1].type;
-                    if (previousType != widgetType)
-                    {
-                        return false;
-                    }
-                }
-                break;
-            }
-            default:
-                // The widget type is not an increment or decrement button
-                return false;
-        }
-
-        attempts++;
-        if (attempts > 2)
-        {
-            // We're 2 buttons up, and no preview or spinner widget was found
-            return false;
-        }
-
-        widgetIndex--;
-        widgetType = w.widgets[widgetIndex].type;
-    }
-
-    WidgetIndex buttonWidgetIndex;
-    WindowWidgetType expectedType;
-
-    switch (widgetType)
-    {
-        case WindowWidgetType::ImgBtn:
-        {
-            auto expectedContent1 = ImageId(SPR_LAND_TOOL_DECREASE, FilterPaletteID::PaletteNull);
-            auto expectedContent2 = ImageId(SPR_LAND_TOOL_INCREASE, FilterPaletteID::PaletteNull);
-
-            auto button1Image = w.widgets[widgetIndex + 1].image;
-            auto button2Image = w.widgets[widgetIndex + 2].image;
-            if (button1Image != expectedContent1 || button2Image != expectedContent2)
-            {
-                return false;
-            }
-
-            buttonWidgetIndex = wheel < 0 ? widgetIndex + 2 : widgetIndex + 1;
-            expectedType = WindowWidgetType::TrnBtn;
-            break;
-        }
-        case WindowWidgetType::Spinner:
-        {
-            auto button1StringID = w.widgets[widgetIndex + 1].text;
-            auto button2StringID = w.widgets[widgetIndex + 2].text;
-            if (button1StringID != STR_NUMERIC_UP || button2StringID != STR_NUMERIC_DOWN)
-            {
-                return false;
-            }
-
-            buttonWidgetIndex = wheel < 0 ? widgetIndex + 1 : widgetIndex + 2;
-            expectedType = WindowWidgetType::Button;
-            break;
-        }
-        default:
-            return false;
-    }
-
-    if (WidgetIsDisabled(w, buttonWidgetIndex))
+    const auto spinnerGroupIndex = getSpinnerGroupWidgetIndex(w, widgetIndex);
+    if (!spinnerGroupIndex.has_value())
     {
         return false;
     }
 
-    auto button1Type = w.widgets[widgetIndex + 1].type;
-    auto button2Type = w.widgets[widgetIndex + 2].type;
-    if (button1Type != expectedType || button2Type != expectedType)
+    const auto entryWidgetType = w.widgets[*spinnerGroupIndex].type;
+    if (entryWidgetType == WindowWidgetType::ImgBtn)
+    {
+        auto expectedContent1 = ImageId(SPR_LAND_TOOL_DECREASE, FilterPaletteID::PaletteNull);
+        auto expectedContent2 = ImageId(SPR_LAND_TOOL_INCREASE, FilterPaletteID::PaletteNull);
+
+        auto button1Image = w.widgets[*spinnerGroupIndex + 1].image;
+        auto button2Image = w.widgets[*spinnerGroupIndex + 2].image;
+        if (button1Image != expectedContent1 || button2Image != expectedContent2)
+        {
+            return false;
+        }
+    }
+    else if (entryWidgetType == WindowWidgetType::Spinner)
+    {
+        auto button1StringId = w.widgets[*spinnerGroupIndex + 1].text;
+        auto button2StringId = w.widgets[*spinnerGroupIndex + 2].text;
+        if (button1StringId != STR_NUMERIC_UP || button2StringId != STR_NUMERIC_DOWN)
+        {
+            return false;
+        }
+    }
+
+    const auto targetWidgetIndex = wheel < 0 ? *spinnerGroupIndex + 1 : *spinnerGroupIndex + 2;
+    if (WidgetIsDisabled(w, targetWidgetIndex))
     {
         return false;
     }
 
-    w.OnMouseDown(buttonWidgetIndex);
+    w.OnMouseDown(targetWidgetIndex);
     return true;
 }
 
diff --git a/src/openrct2-ui/scripting/CustomWindow.cpp b/src/openrct2-ui/scripting/CustomWindow.cpp
index b18c33da2e..42359855df 100644
--- a/src/openrct2-ui/scripting/CustomWindow.cpp
+++ b/src/openrct2-ui/scripting/CustomWindow.cpp
@@ -909,8 +909,8 @@ namespace OpenRCT2::Ui::Windows
                     : _info.Desc.Tabs[page].Widgets[widgetDescIndex - tabWidgetsOffset];
                 auto preWidgetSize = widgetList.size();
                 CreateWidget(widgetList, widgetDesc);
-                auto numWidetsAdded = widgetList.size() - preWidgetSize;
-                for (size_t i = 0; i < numWidetsAdded; i++)
+                auto numWidgetsAdded = widgetList.size() - preWidgetSize;
+                for (size_t i = 0; i < numWidgetsAdded; i++)
                 {
                     _info.WidgetIndexMap.push_back(widgetDescIndex);
                 }