diff --git a/src/changelog/unreleased.md b/src/changelog/unreleased.md
index b1d18d5f88..927d473c99 100644
--- a/src/changelog/unreleased.md
+++ b/src/changelog/unreleased.md
@@ -55,6 +55,7 @@ changelog entry.
   information is available. This "detailed monitors" can be used in `Window::set_fullscreen()` as
   well.
 - On Android, add `{Active,}EventLoopExtAndroid::android_app()` to access the app used to create the loop.
+- Add `ActiveEventLoop::system_theme()`, returning the current system theme.
 
 ### Changed
 
@@ -111,3 +112,4 @@ changelog entry.
 
 - On Web, pen events are now routed through to `WindowEvent::Cursor*`.
 - On macOS, fix panic when releasing not available monitor.
+- On MacOS, return the system theme in `Window::theme()` if no theme override is set.
diff --git a/src/event_loop.rs b/src/event_loop.rs
index f014b56400..8f8a627e28 100644
--- a/src/event_loop.rs
+++ b/src/event_loop.rs
@@ -23,7 +23,7 @@ use crate::application::ApplicationHandler;
 use crate::error::{EventLoopError, OsError};
 use crate::monitor::MonitorHandle;
 use crate::platform_impl;
-use crate::window::{CustomCursor, CustomCursorSource, Window, WindowAttributes};
+use crate::window::{CustomCursor, CustomCursorSource, Theme, Window, WindowAttributes};
 
 /// Provides a way to retrieve events from the system and from the windows that were registered to
 /// the events loop.
@@ -403,6 +403,17 @@ impl ActiveEventLoop {
         self.p.listen_device_events(allowed);
     }
 
+    /// Returns the current system theme.
+    ///
+    /// Returns `None` if it cannot be determined on the current platform.
+    ///
+    /// ## Platform-specific
+    ///
+    /// - **iOS / Android / Wayland / x11 / Orbital:** Unsupported.
+    pub fn system_theme(&self) -> Option<Theme> {
+        self.p.system_theme()
+    }
+
     /// Sets the [`ControlFlow`].
     pub fn set_control_flow(&self, control_flow: ControlFlow) {
         self.p.set_control_flow(control_flow)
diff --git a/src/platform_impl/android/mod.rs b/src/platform_impl/android/mod.rs
index 1f597772ac..3375cc61ab 100644
--- a/src/platform_impl/android/mod.rs
+++ b/src/platform_impl/android/mod.rs
@@ -605,6 +605,11 @@ impl ActiveEventLoop {
     #[inline]
     pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
 
+    #[inline]
+    pub fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
diff --git a/src/platform_impl/apple/appkit/event_loop.rs b/src/platform_impl/apple/appkit/event_loop.rs
index cb070d5734..4bb6fc7f2d 100644
--- a/src/platform_impl/apple/appkit/event_loop.rs
+++ b/src/platform_impl/apple/appkit/event_loop.rs
@@ -17,7 +17,7 @@ use core_foundation::runloop::{
 };
 use objc2::rc::{autoreleasepool, Retained};
 use objc2::runtime::ProtocolObject;
-use objc2::{msg_send_id, ClassType};
+use objc2::{msg_send_id, sel, ClassType};
 use objc2_app_kit::{NSApplication, NSApplicationActivationPolicy, NSWindow};
 use objc2_foundation::{MainThreadMarker, NSObjectProtocol};
 
@@ -32,7 +32,7 @@ use crate::error::EventLoopError;
 use crate::event_loop::{ActiveEventLoop as RootWindowTarget, ControlFlow, DeviceEvents};
 use crate::platform::macos::ActivationPolicy;
 use crate::platform::pump_events::PumpStatus;
-use crate::window::{CustomCursor as RootCustomCursor, CustomCursorSource};
+use crate::window::{CustomCursor as RootCustomCursor, CustomCursorSource, Theme};
 
 #[derive(Default)]
 pub struct PanicInfo {
@@ -103,6 +103,17 @@ impl ActiveEventLoop {
     #[inline]
     pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
 
+    #[inline]
+    pub fn system_theme(&self) -> Option<Theme> {
+        let app = NSApplication::sharedApplication(self.mtm);
+
+        if app.respondsToSelector(sel!(effectiveAppearance)) {
+            Some(super::window_delegate::appearance_to_theme(&app.effectiveAppearance()))
+        } else {
+            Some(Theme::Light)
+        }
+    }
+
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
diff --git a/src/platform_impl/apple/appkit/window_delegate.rs b/src/platform_impl/apple/appkit/window_delegate.rs
index bebe5d66d9..af65f85095 100644
--- a/src/platform_impl/apple/appkit/window_delegate.rs
+++ b/src/platform_impl/apple/appkit/window_delegate.rs
@@ -1623,14 +1623,18 @@ impl WindowDelegate {
     }
 
     pub fn theme(&self) -> Option<Theme> {
-        // Note: We could choose between returning the value of `effectiveAppearance` or
-        // `appearance`, depending on what the user is asking about:
-        // - "how should I render on this particular frame".
-        // - "what is the configuration for this window".
-        //
-        // We choose the latter for consistency with the `set_theme` call, though it might also be
-        // useful to expose the former.
-        Some(appearance_to_theme(unsafe { &*self.window().appearance()? }))
+        unsafe { self.window().appearance() }
+            .map(|appearance| appearance_to_theme(&appearance))
+            .or_else(|| {
+                let mtm = MainThreadMarker::from(self);
+                let app = NSApplication::sharedApplication(mtm);
+
+                if app.respondsToSelector(sel!(effectiveAppearance)) {
+                    Some(super::window_delegate::appearance_to_theme(&app.effectiveAppearance()))
+                } else {
+                    Some(Theme::Light)
+                }
+            })
     }
 
     pub fn set_theme(&self, theme: Option<Theme>) {
@@ -1813,7 +1817,7 @@ fn dark_appearance_name() -> &'static NSString {
     ns_string!("NSAppearanceNameDarkAqua")
 }
 
-fn appearance_to_theme(appearance: &NSAppearance) -> Theme {
+pub fn appearance_to_theme(appearance: &NSAppearance) -> Theme {
     let best_match = appearance.bestMatchFromAppearancesWithNames(&NSArray::from_id_slice(&[
         unsafe { NSAppearanceNameAqua.copy() },
         dark_appearance_name().copy(),
diff --git a/src/platform_impl/apple/uikit/event_loop.rs b/src/platform_impl/apple/uikit/event_loop.rs
index 476fee7483..807fabb2a1 100644
--- a/src/platform_impl/apple/uikit/event_loop.rs
+++ b/src/platform_impl/apple/uikit/event_loop.rs
@@ -24,7 +24,7 @@ use crate::application::ApplicationHandler;
 use crate::error::EventLoopError;
 use crate::event::Event;
 use crate::event_loop::{ActiveEventLoop as RootActiveEventLoop, ControlFlow, DeviceEvents};
-use crate::window::{CustomCursor, CustomCursorSource};
+use crate::window::{CustomCursor, CustomCursorSource, Theme};
 
 #[derive(Debug)]
 pub struct ActiveEventLoop {
@@ -53,6 +53,11 @@ impl ActiveEventLoop {
     #[inline]
     pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
 
+    #[inline]
+    pub fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
diff --git a/src/platform_impl/linux/mod.rs b/src/platform_impl/linux/mod.rs
index b82cf45dd4..abb94963c8 100644
--- a/src/platform_impl/linux/mod.rs
+++ b/src/platform_impl/linux/mod.rs
@@ -864,6 +864,11 @@ impl ActiveEventLoop {
         x11_or_wayland!(match self; Self(evlp) => evlp.listen_device_events(allowed))
     }
 
+    #[inline]
+    pub fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
diff --git a/src/platform_impl/orbital/event_loop.rs b/src/platform_impl/orbital/event_loop.rs
index e2de434320..b8fe496ecf 100644
--- a/src/platform_impl/orbital/event_loop.rs
+++ b/src/platform_impl/orbital/event_loop.rs
@@ -25,7 +25,7 @@ use crate::keyboard::{
     PhysicalKey,
 };
 use crate::window::{
-    CustomCursor as RootCustomCursor, CustomCursorSource, WindowId as RootWindowId,
+    CustomCursor as RootCustomCursor, CustomCursorSource, Theme, WindowId as RootWindowId,
 };
 
 fn convert_scancode(scancode: u8) -> (PhysicalKey, Option<NamedKey>) {
@@ -747,6 +747,11 @@ impl ActiveEventLoop {
     #[inline]
     pub fn listen_device_events(&self, _allowed: DeviceEvents) {}
 
+    #[inline]
+    pub fn system_theme(&self) -> Option<Theme> {
+        None
+    }
+
     #[cfg(feature = "rwh_06")]
     #[inline]
     pub fn raw_display_handle_rwh_06(
diff --git a/src/platform_impl/web/event_loop/window_target.rs b/src/platform_impl/web/event_loop/window_target.rs
index e4e92f4e23..f21a2794d4 100644
--- a/src/platform_impl/web/event_loop/window_target.rs
+++ b/src/platform_impl/web/event_loop/window_target.rs
@@ -611,6 +611,16 @@ impl ActiveEventLoop {
         self.runner.listen_device_events(allowed)
     }
 
+    pub fn system_theme(&self) -> Option<Theme> {
+        backend::is_dark_mode(self.runner.window()).map(|is_dark_mode| {
+            if is_dark_mode {
+                Theme::Dark
+            } else {
+                Theme::Light
+            }
+        })
+    }
+
     pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
         self.runner.set_control_flow(control_flow)
     }
diff --git a/src/platform_impl/windows/dark_mode.rs b/src/platform_impl/windows/dark_mode.rs
index 4e3a826296..46580c42ef 100644
--- a/src/platform_impl/windows/dark_mode.rs
+++ b/src/platform_impl/windows/dark_mode.rs
@@ -122,7 +122,7 @@ fn set_dark_mode_for_window(hwnd: HWND, is_dark_mode: bool) -> bool {
     }
 }
 
-fn should_use_dark_mode() -> bool {
+pub fn should_use_dark_mode() -> bool {
     should_apps_use_dark_mode() && !is_high_contrast()
 }
 
diff --git a/src/platform_impl/windows/event_loop.rs b/src/platform_impl/windows/event_loop.rs
index 7f42f12c0a..05fe1c7283 100644
--- a/src/platform_impl/windows/event_loop.rs
+++ b/src/platform_impl/windows/event_loop.rs
@@ -82,7 +82,7 @@ use crate::platform_impl::platform::{
 };
 use crate::utils::Lazy;
 use crate::window::{
-    CustomCursor as RootCustomCursor, CustomCursorSource, WindowId as RootWindowId,
+    CustomCursor as RootCustomCursor, CustomCursorSource, Theme, WindowId as RootWindowId,
 };
 
 pub(crate) struct WindowData {
@@ -516,6 +516,10 @@ impl ActiveEventLoop {
         raw_input::register_all_mice_and_keyboards_for_raw_input(self.thread_msg_target, allowed);
     }
 
+    pub fn system_theme(&self) -> Option<Theme> {
+        Some(if super::dark_mode::should_use_dark_mode() { Theme::Dark } else { Theme::Light })
+    }
+
     pub(crate) fn set_control_flow(&self, control_flow: ControlFlow) {
         self.runner_shared.set_control_flow(control_flow)
     }
diff --git a/src/window.rs b/src/window.rs
index ab79f8d900..991431247c 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -1367,14 +1367,14 @@ impl Window {
         self.window.maybe_queue_on_main(move |w| w.set_theme(theme))
     }
 
-    /// Returns the current window theme override.
+    /// Returns the current window theme.
     ///
-    /// Returns `None` if the current theme is set as the system default, or if it cannot be
-    /// determined on the current platform.
+    /// Returns `None` if it cannot be determined on the current platform.
     ///
     /// ## Platform-specific
     ///
-    /// - **iOS / Android / Wayland / x11 / Orbital:** Unsupported, returns `None`.
+    /// - **iOS / Android / x11 / Orbital:** Unsupported.
+    /// - **Wayland:** Only returns theme overrides.
     #[inline]
     pub fn theme(&self) -> Option<Theme> {
         let _span = tracing::debug_span!("winit::Window::theme",).entered();