diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4aadc72a8c..011edcaf01 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@ On CallContent make sure to pass onBackPressed to CallAppBar in order to make th
 
 ### ✅ Added
 Add `participantLabelContent` slot to `CallLobby` so the lobby participant label can be hidden (`{}`) or fully customized. Brings the Compose API in line with React's `VideoPreview` slot overrides.
+Add `videoPreviewModifier` parameter to `CallLobby` so callers can override the size, shape, padding, and background of the local video preview box. Defaults preserve the previous responsive height + 12dp rounded corner clip, matching iOS (parent-driven sizing in `GeometryReader`) and React (`className`-driven sizing on `VideoPreview`).
 
 ### ⚠️ Changed
 Deprecate the `CallLobby` overload that takes `labelPosition: Alignment`. Migrate to the new `participantLabelContent` slot; pass `{}` to hide the label or supply a composable to customize content and positioning.
diff --git a/stream-video-android-ui-compose/api/stream-video-android-ui-compose.api b/stream-video-android-ui-compose/api/stream-video-android-ui-compose.api
index 548c217356..3b122c1ca0 100644
--- a/stream-video-android-ui-compose/api/stream-video-android-ui-compose.api
+++ b/stream-video-android-ui-compose/api/stream-video-android-ui-compose.api
@@ -1039,7 +1039,7 @@ public final class io/getstream/video/android/compose/ui/components/call/diagnos
 
 public final class io/getstream/video/android/compose/ui/components/call/lobby/CallLobbyKt {
 	public static final fun CallLobby (Landroidx/compose/ui/Modifier;Lio/getstream/video/android/core/Call;Lio/getstream/video/android/model/User;Landroidx/compose/ui/Alignment;ZZLio/getstream/video/android/core/ParticipantState$Video;Lio/getstream/video/android/compose/permission/VideoPermissionsState;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function3;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function4;Landroidx/compose/runtime/Composer;III)V
-	public static final fun CallLobby (Landroidx/compose/ui/Modifier;Lio/getstream/video/android/core/Call;Lio/getstream/video/android/model/User;ZZLio/getstream/video/android/core/ParticipantState$Video;Lio/getstream/video/android/compose/permission/VideoPermissionsState;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function3;Lkotlin/jvm/functions/Function2;Lkotlin/jvm/functions/Function3;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function4;Landroidx/compose/runtime/Composer;III)V
+	public static final fun CallLobby (Landroidx/compose/ui/Modifier;Lio/getstream/video/android/core/Call;Lio/getstream/video/android/model/User;ZZLio/getstream/video/android/core/ParticipantState$Video;Lio/getstream/video/android/compose/permission/VideoPermissionsState;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function3;Lkotlin/jvm/functions/Function2;Landroidx/compose/ui/Modifier;Lkotlin/jvm/functions/Function3;Lkotlin/jvm/functions/Function1;Lkotlin/jvm/functions/Function4;Landroidx/compose/runtime/Composer;III)V
 }
 
 public final class io/getstream/video/android/compose/ui/components/call/lobby/ComposableSingletons$CallLobbyKt {
diff --git a/stream-video-android-ui-compose/src/main/kotlin/io/getstream/video/android/compose/ui/components/call/lobby/CallLobby.kt b/stream-video-android-ui-compose/src/main/kotlin/io/getstream/video/android/compose/ui/components/call/lobby/CallLobby.kt
index e6cb3ce561..391fa43819 100644
--- a/stream-video-android-ui-compose/src/main/kotlin/io/getstream/video/android/compose/ui/components/call/lobby/CallLobby.kt
+++ b/stream-video-android-ui-compose/src/main/kotlin/io/getstream/video/android/compose/ui/components/call/lobby/CallLobby.kt
@@ -75,6 +75,10 @@ import io.getstream.video.android.ui.common.R
  * @param permissions Android permissions that should be required to render a video call properly.
  * @param onRenderedContent A video renderer, which renders a local video track before joining a call.
  * @param onDisabledContent Content is shown that a local camera is disabled. It displays user avatar by default.
+ * @param videoPreviewModifier Modifier applied to the [Box] that wraps the local video preview. Defaults
+ * to a responsive height (180/280/200dp depending on screen size and orientation), full width, and a
+ * 12dp rounded corner clip. Override to provide custom size, shape, padding, or background — useful
+ * when the preview needs to match a host layout instead of the SDK's default sizing.
  * @param participantLabelContent Slot for the participant label overlaid on the preview. Defaults to a
  * label showing the user's name and microphone state at [Alignment.BottomStart]. Pass `{}` to hide the
  * label entirely, or override to provide custom positioning and content (use [BoxScope.align] inside).
@@ -118,6 +122,7 @@ public fun CallLobby(
     onDisabledContent: @Composable () -> Unit = {
         OnDisabledContent(user = user)
     },
+    videoPreviewModifier: Modifier = defaultVideoPreviewModifier(),
     participantLabelContent: @Composable BoxScope.() -> Unit = {
         DefaultParticipantLabel(
             user = user,
@@ -144,18 +149,10 @@ public fun CallLobby(
     DefaultPermissionHandler(videoPermission = permissions)
 
     MediaPiPLifecycle(call = call, PictureInPictureConfiguration(false, false))
-    val configuration = LocalConfiguration.current
-    val isPortrait = configuration.orientation == Configuration.ORIENTATION_PORTRAIT
-    val screenHeightDp = configuration.screenHeightDp
-
-    val boxModifier = Modifier
-        .responsiveHeight(isPortrait, screenHeightDp)
-        .fillMaxWidth()
-        .clip(RoundedCornerShape(12.dp))
 
     Column(modifier = modifier) {
         Box(
-            modifier = boxModifier,
+            modifier = videoPreviewModifier,
         ) {
             if (isCameraEnabled) {
                 onRenderedContent.invoke(video)
@@ -358,6 +355,16 @@ private fun OnDisabledContent(user: User) {
     }
 }
 
+@Composable
+private fun defaultVideoPreviewModifier(): Modifier {
+    val configuration = LocalConfiguration.current
+    val isPortrait = configuration.orientation == Configuration.ORIENTATION_PORTRAIT
+    return Modifier
+        .responsiveHeight(isPortrait = isPortrait, screenHeightDp = configuration.screenHeightDp)
+        .fillMaxWidth()
+        .clip(RoundedCornerShape(12.dp))
+}
+
 private fun Modifier.responsiveHeight(isPortrait: Boolean, screenHeightDp: Int): Modifier {
     val isSmallDevice = screenHeightDp <= 640
     val height = if (isPortrait && isSmallDevice) {