diff --git a/src/components/card/subtask-list.tsx b/src/components/card/subtask-list.tsx
new file mode 100644
index 0000000..f1d53ce
--- /dev/null
+++ b/src/components/card/subtask-list.tsx
@@ -0,0 +1,139 @@
+"use client";
+
+import { useState, useTransition } from "react";
+import { Plus, X } from "lucide-react";
+
+import { addSubtask, deleteSubtask, toggleSubtask } from "@/app/actions/subtasks";
+import { cn } from "@/lib/cn";
+import type { SubtaskRecord } from "@/lib/pb/types";
+
+export function SubtaskList({
+  cardId,
+  subtasks,
+  editable,
+  clientSlug,
+  projectSlug,
+}: {
+  cardId: string;
+  subtasks: SubtaskRecord[];
+  editable: boolean;
+  clientSlug: string;
+  projectSlug: string;
+}) {
+  const [pending, startTransition] = useTransition();
+  const [draft, setDraft] = useState("");
+
+  const done = subtasks.filter((s) => s.done).length;
+  const percent = subtasks.length
+    ? Math.round((done / subtasks.length) * 100)
+    : 0;
+
+  function submit(event: React.FormEvent) {
+    event.preventDefault();
+    const title = draft.trim();
+    if (!title) return;
+    setDraft("");
+    startTransition(() =>
+      addSubtask({ cardId, title, clientSlug, projectSlug }).then(() => undefined)
+    );
+  }
+
+  return (
+    <section className="space-y-3">
+      <div className="flex items-center gap-3">
+        <h2 className="text-xs font-semibold uppercase tracking-wide text-text-secondary">
+          Checklist
+        </h2>
+        {subtasks.length > 0 && (
+          <>
+            <span className="tabular text-xs text-text-muted">
+              {done}/{subtasks.length}
+            </span>
+            <div
+              className="h-1.5 flex-1 overflow-hidden rounded-full bg-surface-raised"
+              role="progressbar"
+              aria-valuenow={percent}
+              aria-valuemin={0}
+              aria-valuemax={100}
+              aria-label="Checklist progress"
+            >
+              <div
+                className="h-full rounded-full bg-brand transition-[width]"
+                style={{ width: `${percent}%` }}
+              />
+            </div>
+          </>
+        )}
+      </div>
+
+      {subtasks.length === 0 && !editable && (
+        <p className="text-sm text-text-muted">No checklist items yet.</p>
+      )}
+
+      <ul className="space-y-1">
+        {subtasks.map((subtask) => (
+          <li key={subtask.id} className="group flex items-center gap-2.5">
+            <input
+              type="checkbox"
+              checked={subtask.done}
+              disabled={!editable || pending}
+              onChange={(event) =>
+                startTransition(() =>
+                  toggleSubtask({
+                    subtaskId: subtask.id,
+                    done: event.target.checked,
+                    clientSlug,
+                    projectSlug,
+                  }).then(() => undefined)
+                )
+              }
+              className="h-4 w-4 shrink-0 rounded border-border-strong accent-[var(--brand)]"
+            />
+            <span
+              className={cn(
+                "flex-1 text-sm",
+                subtask.done
+                  ? "text-text-muted line-through"
+                  : "text-text-primary"
+              )}
+            >
+              {subtask.title}
+            </span>
+            {editable && (
+              <button
+                type="button"
+                aria-label={`Delete ${subtask.title}`}
+                disabled={pending}
+                onClick={() =>
+                  startTransition(() =>
+                    deleteSubtask({
+                      subtaskId: subtask.id,
+                      clientSlug,
+                      projectSlug,
+                    }).then(() => undefined)
+                  )
+                }
+                className="opacity-0 transition-opacity group-hover:opacity-100 focus-visible:opacity-100"
+              >
+                <X size={14} strokeWidth={2} className="text-text-muted" />
+              </button>
+            )}
+          </li>
+        ))}
+      </ul>
+
+      {editable && (
+        <form onSubmit={submit} className="flex items-center gap-2">
+          <Plus size={14} strokeWidth={2} className="text-text-muted" />
+          <input
+            value={draft}
+            onChange={(event) => setDraft(event.target.value)}
+            placeholder="Add an item"
+            disabled={pending}
+            className="flex-1 bg-transparent text-sm text-text-primary outline-none placeholder:text-text-muted"
+          />
+        </form>
+      )}
+    </section>
+  );
+}
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