diff --git a/include/exec/start_now.hpp b/include/exec/start_now.hpp
index f5f02e02e..b44523168 100644
--- a/include/exec/start_now.hpp
+++ b/include/exec/start_now.hpp
@@ -77,6 +77,7 @@ namespace experimental::execution
 
       constexpr __storage_base(_Env&& __env, std::size_t __pending)
         : __pending_(__pending)
+        , __joiner_(__pending == 0 ? nullptr : &__empty_joiner_)
         , __env_(__mkenv(static_cast<_Env&&>(__env), __source_))
       {}
 
diff --git a/test/exec/async_scope/test_start_now.cpp b/test/exec/async_scope/test_start_now.cpp
index 47f1c80c3..d4d1c1131 100644
--- a/test/exec/async_scope/test_start_now.cpp
+++ b/test/exec/async_scope/test_start_now.cpp
@@ -26,6 +26,14 @@ namespace
     REQUIRE(executed);
   }
 
+  TEST_CASE("start_now zero", "[async_scope][start_now]")
+  {
+    async_scope scope;
+    auto        stg = start_now(scope);
+
+    REQUIRE(sync_wait(stg.async_wait()).has_value());
+  }
+
   TEST_CASE("start_now two", "[async_scope][start_now]")
   {
     bool        executedA{false};