diff --git a/src/rules.ts b/src/rules.ts
index 4983a8ab48..7478556ffd 100644
--- a/src/rules.ts
+++ b/src/rules.ts
@@ -45,8 +45,8 @@ export const other = {
   blockquoteSetextReplace: /\n {0,3}((?:=+|-+) *)(?=\n|$)/g,
   blockquoteSetextReplace2: /^ {0,3}>[ \t]?/gm,
   listReplaceNesting: /^ {1,4}(?=( {4})*[^ ])/g,
-  listIsTask: /^\[[ xX]\] +\S/,
-  listReplaceTask: /^\[[ xX]\] +/,
+  listIsTask: /^\[[ xX]\](?:\s|$)/,
+  listReplaceTask: /^\[[ xX]\][ \t]*/,
   listTaskCheckbox: /\[[ xX]\]/,
   anyLine: /\n.*\n/,
   hrefBrackets: /^<(.*)>$/,
diff --git a/test/specs/new/list_loose_tasks.html b/test/specs/new/list_loose_tasks.html
index 1416f042ef..23e325eb9a 100644
--- a/test/specs/new/list_loose_tasks.html
+++ b/test/specs/new/list_loose_tasks.html
@@ -9,6 +9,6 @@
 <p><input type="checkbox" disabled=""> <pre>Task2</pre></p>
 </li>
 <li>
-<p>[ ]</p>
+<p><input type="checkbox" disabled=""> </p>
 </li>
 </ul>