diff --git a/source/blender/editors/sculpt_paint/grease_pencil_paint.cc b/source/blender/editors/sculpt_paint/grease_pencil_paint.cc
index fb4dc73c0d6..c42e9792f93 100644
--- a/source/blender/editors/sculpt_paint/grease_pencil_paint.cc
+++ b/source/blender/editors/sculpt_paint/grease_pencil_paint.cc
@@ -238,21 +238,28 @@ struct PaintOperationExecutor {
         "hardness",
         bke::AttrDomain::Curve,
         bke::AttributeInitVArray(VArray<float>::ForSingle(1.0f, curves.curves_num())));
-    bke::SpanAttributeWriter<int8_t> start_caps = attributes.lookup_or_add_for_write_span<int8_t>(
-        "start_cap", bke::AttrDomain::Curve);
-    bke::SpanAttributeWriter<int8_t> end_caps = attributes.lookup_or_add_for_write_span<int8_t>(
-        "end_cap", bke::AttrDomain::Curve);
     cyclic.span.last() = false;
     materials.span.last() = material_index;
     hardnesses.span.last() = hardness_;
-    start_caps.span.last() = settings_->caps_type;
-    end_caps.span.last() = settings_->caps_type;
+
+    /* Only set the attribute if the type is not the default or if it already exists. */
+    if (settings_->caps_type != GP_STROKE_CAP_TYPE_ROUND || attributes.contains("start_cap")) {
+      bke::SpanAttributeWriter<int8_t> start_caps =
+          attributes.lookup_or_add_for_write_span<int8_t>("start_cap", bke::AttrDomain::Curve);
+      start_caps.span.last() = settings_->caps_type;
+      start_caps.finish();
+    }
+
+    if (settings_->caps_type != GP_STROKE_CAP_TYPE_ROUND || attributes.contains("end_cap")) {
+      bke::SpanAttributeWriter<int8_t> end_caps = attributes.lookup_or_add_for_write_span<int8_t>(
+          "end_cap", bke::AttrDomain::Curve);
+      end_caps.span.last() = settings_->caps_type;
+      end_caps.finish();
+    }
 
     cyclic.finish();
     materials.finish();
     hardnesses.finish();
-    start_caps.finish();
-    end_caps.finish();
 
     curves.curve_types_for_write().last() = CURVE_TYPE_POLY;
     curves.update_curve_types();