diff --git a/libs/vkd3d-shader/fx.c b/libs/vkd3d-shader/fx.c
index 01df1735..0aa0adf0 100644
--- a/libs/vkd3d-shader/fx.c
+++ b/libs/vkd3d-shader/fx.c
@@ -205,6 +205,7 @@ struct fx_write_context
     uint32_t sampler_state_count;
     uint32_t depth_stencil_state_count;
     uint32_t rasterizer_state_count;
+    uint32_t blend_state_count;
     int status;
 
     bool child_effect;
@@ -755,6 +756,10 @@ static uint32_t write_fx_4_type(const struct hlsl_type *type, struct fx_write_co
     {
         put_u32_unaligned(buffer, 3);
     }
+    else if (type->class == HLSL_CLASS_BLEND_STATE)
+    {
+        put_u32_unaligned(buffer, 2);
+    }
     else if (hlsl_is_numeric_type(type))
     {
         numeric_desc = get_fx_4_numeric_type_description(type, fx);
@@ -2082,6 +2087,11 @@ static void write_fx_4_object_variable(struct hlsl_ir_var *var, struct fx_write_
             fx->rasterizer_state_count += elements_count;
             break;
 
+        case HLSL_CLASS_BLEND_STATE:
+            write_fx_4_state_object_initializer(var, fx);
+            fx->blend_state_count += elements_count;
+            break;
+
         default:
             hlsl_fixme(ctx, &ctx->location, "Writing initializer for object class %u is not implemented.",
                     type->class);
@@ -2183,6 +2193,7 @@ static bool is_supported_object_variable(const struct hlsl_ctx *ctx, const struc
         case HLSL_CLASS_RENDER_TARGET_VIEW:
         case HLSL_CLASS_SAMPLER:
         case HLSL_CLASS_TEXTURE:
+        case HLSL_CLASS_BLEND_STATE:
             return true;
         case HLSL_CLASS_COMPUTE_SHADER:
         case HLSL_CLASS_DOMAIN_SHADER:
@@ -2253,7 +2264,7 @@ static int hlsl_fx_4_write(struct hlsl_ctx *ctx, struct vkd3d_shader_code *out)
     put_u32(&buffer, 0); /* String count. */
     put_u32(&buffer, fx.texture_count);
     put_u32(&buffer, fx.depth_stencil_state_count);
-    put_u32(&buffer, 0); /* Blend state count. */
+    put_u32(&buffer, fx.blend_state_count);
     put_u32(&buffer, fx.rasterizer_state_count);
     put_u32(&buffer, fx.sampler_state_count);
     put_u32(&buffer, fx.rtv_count);
@@ -2311,7 +2322,7 @@ static int hlsl_fx_5_write(struct hlsl_ctx *ctx, struct vkd3d_shader_code *out)
     put_u32(&buffer, 0); /* String count. */
     put_u32(&buffer, fx.texture_count);
     put_u32(&buffer, fx.depth_stencil_state_count);
-    put_u32(&buffer, 0); /* Blend state count. */
+    put_u32(&buffer, fx.blend_state_count);
     put_u32(&buffer, fx.rasterizer_state_count);
     put_u32(&buffer, fx.sampler_state_count);
     put_u32(&buffer, fx.rtv_count);
diff --git a/tests/hlsl/effect-variables-fx_4.shader_test b/tests/hlsl/effect-variables-fx_4.shader_test
index 16a04210..9b2e6918 100644
--- a/tests/hlsl/effect-variables-fx_4.shader_test
+++ b/tests/hlsl/effect-variables-fx_4.shader_test
@@ -40,3 +40,6 @@ SamplerState sampler7 { Texture = t7; };
 SamplerState sampler8 { Texture = t8; };
 SamplerState sampler9 { Texture = t9; };
 SamplerState sampler10 { Texture = t10; };
+
+[effect]
+BlendState bs;
diff --git a/tests/hlsl/effect-variables-fx_5.shader_test b/tests/hlsl/effect-variables-fx_5.shader_test
index b815e157..bc38d77e 100644
--- a/tests/hlsl/effect-variables-fx_5.shader_test
+++ b/tests/hlsl/effect-variables-fx_5.shader_test
@@ -40,3 +40,6 @@ SamplerState sampler7 { Texture = t7; };
 SamplerState sampler8 { Texture = t8; };
 SamplerState sampler9 { Texture = t9; };
 SamplerState sampler10 { Texture = t10; };
+
+[effect]
+BlendState bs;