diff --git a/src/vulkan/wsi/wsi_common_win32.cpp b/src/vulkan/wsi/wsi_common_win32.cpp
index e614dae9782..d8033ef1533 100644
--- a/src/vulkan/wsi/wsi_common_win32.cpp
+++ b/src/vulkan/wsi/wsi_common_win32.cpp
@@ -209,7 +209,8 @@ wsi_win32_surface_get_capabilities(VkIcdSurfaceBase *surf,
 
    caps->supportedCompositeAlpha =
       VK_COMPOSITE_ALPHA_OPAQUE_BIT_KHR |
-      VK_COMPOSITE_ALPHA_PRE_MULTIPLIED_BIT_KHR;
+      VK_COMPOSITE_ALPHA_PRE_MULTIPLIED_BIT_KHR |
+      VK_COMPOSITE_ALPHA_POST_MULTIPLIED_BIT_KHR;
 
    caps->supportedUsageFlags = wsi_caps_get_image_usage();
 
@@ -751,6 +752,22 @@ wsi_win32_surface_create_swapchain_dxgi(
    ID3D12CommandQueue *queue =
       (ID3D12CommandQueue *)wsi->wsi->win32.get_d3d12_command_queue(device);
 
+   DXGI_ALPHA_MODE alpha_mode;
+   switch (create_info->compositeAlpha) {
+   case VK_COMPOSITE_ALPHA_OPAQUE_BIT_KHR:
+      alpha_mode = DXGI_ALPHA_MODE_IGNORE;
+      break;
+   case VK_COMPOSITE_ALPHA_PRE_MULTIPLIED_BIT_KHR:
+      alpha_mode = DXGI_ALPHA_MODE_PREMULTIPLIED;
+      break;
+   case VK_COMPOSITE_ALPHA_POST_MULTIPLIED_BIT_KHR:
+      alpha_mode = DXGI_ALPHA_MODE_STRAIGHT;
+      break;
+   default:
+      alpha_mode = DXGI_ALPHA_MODE_UNSPECIFIED;
+      break;
+   }
+
    DXGI_SWAP_CHAIN_DESC1 desc = {
       create_info->imageExtent.width,
       create_info->imageExtent.height,
@@ -761,7 +778,7 @@ wsi_win32_surface_create_swapchain_dxgi(
       create_info->minImageCount,
       DXGI_SCALING_STRETCH,
       DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL,
-      DXGI_ALPHA_MODE_UNSPECIFIED,
+      alpha_mode,
       chain->base.present_mode == VK_PRESENT_MODE_IMMEDIATE_KHR ?
          DXGI_SWAP_CHAIN_FLAG_ALLOW_TEARING : 0u
    };