diff --git a/src/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/InitializeEvolvedVariables.hpp b/src/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/InitializeEvolvedVariables.hpp
index 03dea963b43e5..857ec07cc3d21 100644
--- a/src/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/InitializeEvolvedVariables.hpp
+++ b/src/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/InitializeEvolvedVariables.hpp
@@ -33,6 +33,7 @@ struct InitializeEvolvedVariables {
 
   using simple_tags =
       tmpl::list<variables_tag, dt_variables_tag, Tags::CurrentIteration,
+                 Tags::ExpirationTime,
                  ::Tags::HistoryEvolvedVariables<variables_tag>>;
   using return_tags = simple_tags;
 
@@ -40,8 +41,9 @@ struct InitializeEvolvedVariables {
   using const_global_cache_tags = tmpl::list<>;
   using mutable_global_cache_tags = tmpl::list<>;
   using simple_tags_from_options = tmpl::list<Tags::InitialPositionAndVelocity>;
-  using argument_tags = tmpl::list<::Tags::TimeStepper<TimeStepper>,
-                                   Tags::InitialPositionAndVelocity>;
+  using argument_tags =
+      tmpl::list<::Tags::TimeStepper<TimeStepper>,
+                 Tags::InitialPositionAndVelocity, ::Tags::Time>;
   static void apply(
       const gsl::not_null<Variables<
           tmpl::list<Tags::EvolvedPosition<Dim>, Tags::EvolvedVelocity<Dim>>>*>
@@ -51,11 +53,15 @@ struct InitializeEvolvedVariables {
                                ::Tags::dt<Tags::EvolvedVelocity<Dim>>>>*>
           dt_evolved_vars,
       const gsl::not_null<size_t*> current_iteration,
+      const gsl::not_null<double*> expiration_time,
       const gsl::not_null<::Tags::HistoryEvolvedVariables<variables_tag>::type*>
           time_stepper_history,
       const TimeStepper& time_stepper,
-      const std::array<tnsr::I<double, Dim>, 2>& initial_pos_and_vel) {
+      const std::array<tnsr::I<double, Dim>, 2>& initial_pos_and_vel,
+      const double initial_time) {
     *current_iteration = 0;
+    *expiration_time = initial_time + 1e-10;
+
     const size_t starting_order =
         time_stepper.number_of_past_steps() == 0 ? time_stepper.order() : 1;
     *time_stepper_history =
diff --git a/src/Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp b/src/Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp
index deaa1452ca21d..6ecef17bdb8c9 100644
--- a/src/Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp
+++ b/src/Evolution/Systems/CurvedScalarWave/Worldtube/Tags.hpp
@@ -355,6 +355,21 @@ struct CurrentIteration : db::SimpleTag {
   using type = size_t;
 };
 
+/*!
+ * \brief The current expiration time of the functions of time which are
+ * controlled by the worldtube singleton.
+ */
+struct ExpirationTime : db::SimpleTag {
+  using type = double;
+};
+
+/*!
+ * \brief The current worldtube radius held by the singleton.
+ */
+struct WorldtubeRadius : db::SimpleTag {
+  using type = double;
+};
+
 /*!
  * \brief The initial position and velocity of the scalar charge in inertial
  * coordinates.
diff --git a/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/Test_InitializeEvolvedVariables.cpp b/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/Test_InitializeEvolvedVariables.cpp
index be04765a73796..a8736cc446648 100644
--- a/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/Test_InitializeEvolvedVariables.cpp
+++ b/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/Test_InitializeEvolvedVariables.cpp
@@ -7,6 +7,7 @@
 #include "Evolution/Systems/CurvedScalarWave/Worldtube/SingletonActions/InitializeEvolvedVariables.hpp"
 #include "Framework/TestingFramework.hpp"
 #include "Time/Tags/HistoryEvolvedVariables.hpp"
+#include "Time/Tags/Time.hpp"
 #include "Time/Tags/TimeStepper.hpp"
 #include "Time/TimeSteppers/AdamsBashforth.hpp"
 #include "Time/TimeSteppers/TimeStepper.hpp"
@@ -21,19 +22,22 @@ SPECTRE_TEST_CASE(
   const tnsr::I<double, 3> initial_pos{{1., 2., 3.}};
   const tnsr::I<double, 3> initial_vel{{4., 5., 6.}};
   const size_t current_iteration = 77;
+  const double expiration_time = 1234.;
+  const double initial_time = 0.;
   auto box =
       db::create<db::AddSimpleTags<
                      variables_tag, dt_variables_tag,
                      ::Tags::HistoryEvolvedVariables<variables_tag>,
                      ::Tags::ConcreteTimeStepper<TimeStepper>,
-                     Tags::InitialPositionAndVelocity, Tags::CurrentIteration>,
+                     Tags::InitialPositionAndVelocity, Tags::CurrentIteration,
+                     Tags::ExpirationTime, ::Tags::Time>,
                  time_stepper_ref_tags<TimeStepper>>(
           variables_tag::type{}, dt_variables_tag::type{},
           TimeSteppers::History<variables_tag::type>{},
           static_cast<std::unique_ptr<TimeStepper>>(
               std::make_unique<TimeSteppers::AdamsBashforth>(4)),
           std::array<tnsr::I<double, 3>, 2>{{initial_pos, initial_vel}},
-          current_iteration);
+          current_iteration, expiration_time, initial_time);
 
   db::mutate_apply<Initialization::InitializeEvolvedVariables>(
       make_not_null(&box));
@@ -47,6 +51,7 @@ SPECTRE_TEST_CASE(
   CHECK(db::get<::Tags::HistoryEvolvedVariables<variables_tag>>(box) ==
         TimeSteppers::History<variables_tag::type>(1));
   CHECK(get<Tags::CurrentIteration>(box) == 0);
+  CHECK(get<Tags::ExpirationTime>(box) == initial_time + 1e-10);
 }
 }  // namespace
 }  // namespace CurvedScalarWave::Worldtube
diff --git a/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/Test_Tags.cpp b/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/Test_Tags.cpp
index 24ccde600cba8..ba4070775dc92 100644
--- a/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/Test_Tags.cpp
+++ b/tests/Unit/Evolution/Systems/CurvedScalarWave/Worldtube/Test_Tags.cpp
@@ -731,6 +731,10 @@ SPECTRE_TEST_CASE("Unit.Evolution.Systems.CurvedScalarWave.Worldtube.Tags",
       "Charge");
   TestHelpers::db::test_simple_tag<CurvedScalarWave::Worldtube::Tags::Mass>(
       "Mass");
+  TestHelpers::db::test_simple_tag<
+      CurvedScalarWave::Worldtube::Tags::ExpirationTime>("ExpirationTime");
+  TestHelpers::db::test_simple_tag<
+      CurvedScalarWave::Worldtube::Tags::WorldtubeRadius>("WorldtubeRadius");
   TestHelpers::db::test_simple_tag<
       CurvedScalarWave::Worldtube::Tags::MaxIterations>("MaxIterations");
   TestHelpers::db::test_simple_tag<