diff --git a/include/openmc/physics_common.h b/include/openmc/physics_common.h
index e38a3c7f8..b0e395c1e 100644
--- a/include/openmc/physics_common.h
+++ b/include/openmc/physics_common.h
@@ -13,5 +13,9 @@ namespace openmc {
 //! \param[in] weight_survive Weight assigned to particles that survive
 void russian_roulette(Particle& p, double weight_survive);
 
+//! \brief Performs the global russian roulette operation on a particle
+//! \param[in,out] p  Particle object
+void apply_russian_roulette(Particle& p);
+
 } // namespace openmc
 #endif // OPENMC_PHYSICS_COMMON_H
diff --git a/include/openmc/weight_windows.h b/include/openmc/weight_windows.h
index 97abcfe82..42846f9d1 100644
--- a/include/openmc/weight_windows.h
+++ b/include/openmc/weight_windows.h
@@ -25,17 +25,6 @@ enum class WeightWindowUpdateMethod { MAGIC, FW_CADIS };
 
 constexpr double DEFAULT_WEIGHT_CUTOFF {1.0e-38}; // default low weight cutoff
 
-//==============================================================================
-// Non-member functions
-//==============================================================================
-
-//! Apply weight windows to a particle
-//! \param[in] p  Particle to apply weight windows to
-void apply_weight_windows(Particle& p);
-
-//! Free memory associated with weight windows
-void free_memory_weight_windows();
-
 //==============================================================================
 // Global variables
 //==============================================================================
@@ -137,7 +126,7 @@ public:
 
   //! Retrieve the weight window for a particle
   //! \param[in] p  Particle to get weight window for
-  WeightWindow get_weight_window(const Particle& p) const;
+  std::pair<bool, WeightWindow> get_weight_window(const Particle& p) const;
 
   std::array<int, 2> bounds_size() const;
 
@@ -236,6 +225,26 @@ public:
   double ratio_ {5.0};     //<! ratio of lower to upper weight window bounds
 };
 
+//==============================================================================
+// Non-member functions
+//==============================================================================
+
+//! Apply weight windows to a particle
+//! \param[in] p  Particle to apply weight windows to
+void apply_weight_windows(Particle& p);
+
+//! Apply weight window to a particle
+//! \param[in] p  Particle to apply weight window to
+//! \param[in] weight_window WeightWindow to apply
+void apply_weight_window(Particle& p, WeightWindow weight_window);
+
+//! Free memory associated with weight windows
+void free_memory_weight_windows();
+
+//! Search weight window that apply to a particle
+//! \param[in]  p  Particle to search weight window for
+std::pair<bool, WeightWindow> search_weight_window(const Particle& p);
+
 //! Finalize variance reduction objects after all inputs have been read
 void finalize_variance_reduction();
 
diff --git a/src/physics.cpp b/src/physics.cpp
index c9737205c..72b4a6611 100644
--- a/src/physics.cpp
+++ b/src/physics.cpp
@@ -64,8 +64,17 @@ void collision(Particle& p)
     fatal_error("Unsupported particle PDG for collision sampling.");
   }
 
-  if (settings::weight_window_checkpoint_collision)
-    apply_weight_windows(p);
+  if (settings::weight_windows_on) {
+    auto [ww_found, ww] = search_weight_window(p);
+    if (!ww_found && p.type() == ParticleType::neutron()) {
+      // if the weight window is not valid, apply russian roulette for neutrons
+      // (regardless of weight window collision checkpoint setting)
+      apply_russian_roulette(p);
+    } else if (settings::weight_window_checkpoint_collision) {
+      // if collision checkpointing is on, apply weight window
+      apply_weight_window(p, ww);
+    }
+  }
 
   // Kill particle if energy falls below cutoff
   int type = p.type().transport_index();
@@ -156,18 +165,9 @@ void sample_neutron_reaction(Particle& p)
     advance_prn_seed(data::nuclides.size(), &p.seeds(STREAM_URR_PTABLE));
   }
 
-  // Play russian roulette if survival biasing is turned on
-  if (settings::survival_biasing) {
-    // if survival normalization is on, use normalized weight cutoff and
-    // normalized weight survive
-    if (settings::survival_normalization) {
-      if (p.wgt() < settings::weight_cutoff * p.wgt_born()) {
-        russian_roulette(p, settings::weight_survive * p.wgt_born());
-      }
-    } else if (p.wgt() < settings::weight_cutoff) {
-      russian_roulette(p, settings::weight_survive);
-    }
-  }
+  // Play russian roulette if there are no weight windows
+  if (!settings::weight_windows_on)
+    apply_russian_roulette(p);
 }
 
 void create_fission_sites(Particle& p, int i_nuclide, const Reaction& rx)
diff --git a/src/physics_common.cpp b/src/physics_common.cpp
index e25ae6b97..10760ce2d 100644
--- a/src/physics_common.cpp
+++ b/src/physics_common.cpp
@@ -18,4 +18,20 @@ void russian_roulette(Particle& p, double weight_survive)
   }
 }
 
+void apply_russian_roulette(Particle& p)
+{
+  // Exit if survival biasing is turned off
+  if (!settings::survival_biasing)
+    return;
+
+  // if survival normalization is on, use normalized weight cutoff and
+  // normalized weight survive
+  if (settings::survival_normalization) {
+    if (p.wgt() < settings::weight_cutoff * p.wgt_born()) {
+      russian_roulette(p, settings::weight_survive * p.wgt_born());
+    }
+  } else if (p.wgt() < settings::weight_cutoff) {
+    russian_roulette(p, settings::weight_survive);
+  }
+}
 } // namespace openmc
diff --git a/src/physics_mg.cpp b/src/physics_mg.cpp
index 32ae10a60..6991c7365 100644
--- a/src/physics_mg.cpp
+++ b/src/physics_mg.cpp
@@ -32,8 +32,17 @@ void collision_mg(Particle& p)
   // Sample the reaction type
   sample_reaction(p);
 
-  if (settings::weight_window_checkpoint_collision)
-    apply_weight_windows(p);
+  if (settings::weight_windows_on) {
+    auto [ww_found, ww] = search_weight_window(p);
+    if (!ww_found && p.type() == ParticleType::neutron()) {
+      // if the weight window is not valid, apply russian roulette
+      // (regardless of weight window collision checkpoint setting)
+      apply_russian_roulette(p);
+    } else if (settings::weight_window_checkpoint_collision) {
+      // if collision checkpointing is on, apply weight window
+      apply_weight_window(p, ww);
+    }
+  }
 
   // Display information about collision
   if ((settings::verbosity >= 10) || p.trace()) {
@@ -67,18 +76,9 @@ void sample_reaction(Particle& p)
   // Sample a scattering event to determine the energy of the exiting neutron
   scatter(p);
 
-  // Play Russian roulette if survival biasing is turned on
-  if (settings::survival_biasing) {
-    // if survival normalization is applicable, use normalized weight cutoff and
-    // normalized weight survive
-    if (settings::survival_normalization) {
-      if (p.wgt() < settings::weight_cutoff * p.wgt_born()) {
-        russian_roulette(p, settings::weight_survive * p.wgt_born());
-      }
-    } else if (p.wgt() < settings::weight_cutoff) {
-      russian_roulette(p, settings::weight_survive);
-    }
-  }
+  // Play russian roulette if there are no weight windows
+  if (!settings::weight_windows_on)
+    apply_russian_roulette(p);
 }
 
 void scatter(Particle& p)
diff --git a/src/random_ray/flat_source_domain.cpp b/src/random_ray/flat_source_domain.cpp
index b881ced71..1a6e7c0be 100644
--- a/src/random_ray/flat_source_domain.cpp
+++ b/src/random_ray/flat_source_domain.cpp
@@ -843,7 +843,7 @@ void FlatSourceDomain::output_to_vtk() const
           voxel_positions[z * Ny * Nx + y * Nx + x] = sample;
 
           if (variance_reduction::weight_windows.size() == 1) {
-            WeightWindow ww =
+            auto [ww_found, ww] =
               variance_reduction::weight_windows[0]->get_weight_window(p);
             float weight = ww.lower_weight;
             weight_windows[z * Ny * Nx + y * Nx + x] = weight;
diff --git a/src/settings.cpp b/src/settings.cpp
index b6a9ab953..ee8edd4a5 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -1266,6 +1266,13 @@ void read_settings_xml(pugi::xml_node root)
     }
   }
 
+  if (weight_windows_on) {
+    if (!weight_window_checkpoint_surface &&
+        !weight_window_checkpoint_collision)
+      fatal_error(
+        "Weight Windows are enabled but there are no valid checkpoints.");
+  }
+
   if (check_for_node(root, "use_decay_photons")) {
     settings::use_decay_photons =
       get_node_value_bool(root, "use_decay_photons");
diff --git a/src/weight_windows.cpp b/src/weight_windows.cpp
index c05169132..c00872e56 100644
--- a/src/weight_windows.cpp
+++ b/src/weight_windows.cpp
@@ -44,108 +44,6 @@ openmc::vector<unique_ptr<WeightWindowsGenerator>> weight_windows_generators;
 
 } // namespace variance_reduction
 
-//==============================================================================
-// Non-member functions
-//==============================================================================
-
-void apply_weight_windows(Particle& p)
-{
-  if (!settings::weight_windows_on)
-    return;
-
-  // WW on photon and neutron only
-  if (!p.type().is_neutron() && !p.type().is_photon())
-    return;
-
-  // skip dead or no energy
-  if (p.E() <= 0 || !p.alive())
-    return;
-
-  bool in_domain = false;
-  // TODO: this is a linear search - should do something more clever
-  WeightWindow weight_window;
-  for (const auto& ww : variance_reduction::weight_windows) {
-    weight_window = ww->get_weight_window(p);
-    if (weight_window.is_valid())
-      break;
-  }
-
-  // If particle has not yet had its birth weight window value set, set it to
-  // the current weight window (or 1.0 if not born in a weight window).
-  if (p.wgt_ww_born() == -1.0) {
-    if (weight_window.is_valid()) {
-      p.wgt_ww_born() =
-        (weight_window.lower_weight + weight_window.upper_weight) / 2;
-    } else {
-      p.wgt_ww_born() = 1.0;
-    }
-  }
-
-  // particle is not in any of the ww domains, do nothing
-  if (!weight_window.is_valid())
-    return;
-
-  // Normalize weight windows based on particle's starting weight
-  // and the value of the weight window the particle was born in.
-  weight_window.scale(p.wgt_born() / p.wgt_ww_born());
-
-  // get the paramters
-  double weight = p.wgt();
-
-  // first check to see if particle should be killed for weight cutoff
-  if (p.wgt() < weight_window.weight_cutoff) {
-    p.wgt() = 0.0;
-    return;
-  }
-
-  // check if particle is far above current weight window
-  // only do this if the factor is not already set on the particle and a
-  // maximum lower bound ratio is specified
-  if (p.ww_factor() == 0.0 && weight_window.max_lb_ratio > 1.0 &&
-      p.wgt() > weight_window.lower_weight * weight_window.max_lb_ratio) {
-    p.ww_factor() =
-      p.wgt() / (weight_window.lower_weight * weight_window.max_lb_ratio);
-  }
-
-  // move weight window closer to the particle weight if needed
-  if (p.ww_factor() > 1.0)
-    weight_window.scale(p.ww_factor());
-
-  // if particle's weight is above the weight window split until they are within
-  // the window
-  if (weight > weight_window.upper_weight) {
-    // do not further split the particle if above the limit
-    if (p.n_split() >= settings::max_history_splits)
-      return;
-
-    double n_split = std::ceil(weight / weight_window.upper_weight);
-    double max_split = weight_window.max_split;
-    n_split = std::min(n_split, max_split);
-
-    p.n_split() += n_split;
-
-    // Create secondaries and divide weight among all particles
-    int i_split = std::round(n_split);
-    for (int l = 0; l < i_split - 1; l++) {
-      p.split(weight / n_split);
-    }
-    // remaining weight is applied to current particle
-    p.wgt() = weight / n_split;
-
-  } else if (weight <= weight_window.lower_weight) {
-    // if the particle weight is below the window, play Russian roulette
-    double weight_survive =
-      std::min(weight * weight_window.max_split, weight_window.survival_weight);
-    russian_roulette(p, weight_survive);
-  } // else particle is in the window, continue as normal
-}
-
-void free_memory_weight_windows()
-{
-  variance_reduction::ww_map.clear();
-  variance_reduction::weight_windows.clear();
-}
-
 //==============================================================================
 // WeightWindowSettings implementation
 //==============================================================================
@@ -375,27 +273,28 @@ void WeightWindows::set_mesh(const Mesh* mesh)
   set_mesh(model::mesh_map[mesh->id_]);
 }
 
-WeightWindow WeightWindows::get_weight_window(const Particle& p) const
+std::pair<bool, WeightWindow> WeightWindows::get_weight_window(
+  const Particle& p) const
 {
   // check for particle type
   if (particle_type_ != p.type()) {
-    return {};
+    return {false, {}};
   }
 
+  // particle energy
+  double E = p.E();
+
+  // check to make sure energy is in range, expects sorted energy values
+  if (E < energy_bounds_.front() || E > energy_bounds_.back())
+    return {false, {}};
+
   // Get mesh index for particle's position
   const auto& mesh = this->mesh();
   int mesh_bin = mesh->get_bin(p.r());
 
   // particle is outside the weight window mesh
   if (mesh_bin < 0)
-    return {};
-
-  // particle energy
-  double E = p.E();
-
-  // check to make sure energy is in range, expects sorted energy values
-  if (E < energy_bounds_.front() || E > energy_bounds_.back())
-    return {};
+    return {false, {}};
 
   // get the mesh bin in energy group
   int energy_bin =
@@ -410,7 +309,7 @@ WeightWindow WeightWindows::get_weight_window(const Particle& p) const
   ww.max_lb_ratio = max_lb_ratio_;
   ww.max_split = max_split_;
   ww.weight_cutoff = weight_cutoff_;
-  return ww;
+  return {true, ww};
 }
 
 std::array<int, 2> WeightWindows::bounds_size() const
@@ -1023,6 +922,115 @@ void WeightWindowsGenerator::update() const
 // Non-member functions
 //==============================================================================
 
+std::pair<bool, WeightWindow> search_weight_window(const Particle& p)
+{
+  // TODO: this is a linear search - should do something more clever
+  for (const auto& ww : variance_reduction::weight_windows) {
+    auto [ww_found, weight_window] = ww->get_weight_window(p);
+    if (ww_found)
+      return {true, weight_window};
+  }
+  return {false, {}};
+}
+
+void apply_weight_windows(Particle& p)
+{
+  if (!settings::weight_windows_on)
+    return;
+
+  // WW on photon and neutron only
+  if (!p.type().is_neutron() && !p.type().is_photon())
+    return;
+
+  // skip dead or no energy
+  if (p.E() <= 0 || !p.alive())
+    return;
+
+  auto [ww_found, ww] = search_weight_window(p);
+  if (ww_found && ww.is_valid()) {
+    apply_weight_window(p, ww);
+  } else {
+    if (p.wgt_ww_born() == -1.0)
+      p.wgt_ww_born() = 1.0;
+  }
+}
+
+void apply_weight_window(Particle& p, WeightWindow weight_window)
+{
+  if (!weight_window.is_valid())
+    return;
+
+  // skip dead or no energy
+  if (p.E() <= 0 || !p.alive())
+    return;
+
+  // If particle has not yet had its birth weight window value set, set it to
+  // the current weight window.
+  if (p.wgt_ww_born() == -1.0)
+    p.wgt_ww_born() =
+      (weight_window.lower_weight + weight_window.upper_weight) / 2;
+
+  // Normalize weight windows based on particle's starting weight
+  // and the value of the weight window the particle was born in.
+  weight_window.scale(p.wgt_born() / p.wgt_ww_born());
+
+  // get the paramters
+  double weight = p.wgt();
+
+  // first check to see if particle should be killed for weight cutoff
+  if (p.wgt() < weight_window.weight_cutoff) {
+    p.wgt() = 0.0;
+    return;
+  }
+
+  // check if particle is far above current weight window
+  // only do this if the factor is not already set on the particle and a
+  // maximum lower bound ratio is specified
+  if (p.ww_factor() == 0.0 && weight_window.max_lb_ratio > 1.0 &&
+      p.wgt() > weight_window.lower_weight * weight_window.max_lb_ratio) {
+    p.ww_factor() =
+      p.wgt() / (weight_window.lower_weight * weight_window.max_lb_ratio);
+  }
+
+  // move weight window closer to the particle weight if needed
+  if (p.ww_factor() > 1.0)
+    weight_window.scale(p.ww_factor());
+
+  // if particle's weight is above the weight window split until they are within
+  // the window
+  if (weight > weight_window.upper_weight) {
+    // do not further split the particle if above the limit
+    if (p.n_split() >= settings::max_history_splits)
+      return;
+
+    double n_split = std::ceil(weight / weight_window.upper_weight);
+    double max_split = weight_window.max_split;
+    n_split = std::min(n_split, max_split);
+
+    p.n_split() += n_split;
+
+    // Create secondaries and divide weight among all particles
+    int i_split = std::round(n_split);
+    for (int l = 0; l < i_split - 1; l++) {
+      p.split(weight / n_split);
+    }
+    // remaining weight is applied to current particle
+    p.wgt() = weight / n_split;
+
+  } else if (weight <= weight_window.lower_weight) {
+    // if the particle weight is below the window, play Russian roulette
+    double weight_survive =
+      std::min(weight * weight_window.max_split, weight_window.survival_weight);
+    russian_roulette(p, weight_survive);
+  } // else particle is in the window, continue as normal
+}
+
+void free_memory_weight_windows()
+{
+  variance_reduction::ww_map.clear();
+  variance_reduction::weight_windows.clear();
+}
+
 void finalize_variance_reduction()
 {
   for (const auto& wwg : variance_reduction::weight_windows_generators) {
diff --git a/tests/regression_tests/weightwindows/survival_biasing/__init__.py b/tests/regression_tests/weightwindows/survival_biasing/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/regression_tests/weightwindows/survival_biasing/inputs_true.dat b/tests/regression_tests/weightwindows/survival_biasing/inputs_true.dat
new file mode 100644
index 000000000..d5aa135d4
--- /dev/null
+++ b/tests/regression_tests/weightwindows/survival_biasing/inputs_true.dat
@@ -0,0 +1,68 @@
+<?xml version='1.0' encoding='utf-8'?>
+<model>
+  <materials>
+    <material id="1" name="Tungsten">
+      <density value="19.25" units="g/cm3"/>
+      <nuclide name="W180" ao="0.0012"/>
+      <nuclide name="W182" ao="0.265"/>
+      <nuclide name="W183" ao="0.1431"/>
+      <nuclide name="W184" ao="0.3064"/>
+      <nuclide name="W186" ao="0.2843"/>
+    </material>
+  </materials>
+  <geometry>
+    <cell id="1" material="1" region="1 -2 3 -4 5 -6" universe="1"/>
+    <surface id="1" type="x-plane" boundary="reflective" coeffs="0.0"/>
+    <surface id="2" type="x-plane" boundary="vacuum" coeffs="160.0"/>
+    <surface id="3" type="y-plane" boundary="reflective" coeffs="0.0"/>
+    <surface id="4" type="y-plane" boundary="reflective" coeffs="160.0"/>
+    <surface id="5" type="z-plane" boundary="reflective" coeffs="0.0"/>
+    <surface id="6" type="z-plane" boundary="reflective" coeffs="160.0"/>
+  </geometry>
+  <settings>
+    <run_mode>fixed source</run_mode>
+    <particles>50</particles>
+    <batches>5</batches>
+    <source type="independent" strength="1.0" particle="neutron">
+      <space type="cartesian">
+        <x type="discrete">
+          <parameters>0.01 1.0</parameters>
+        </x>
+        <y type="uniform" parameters="0.0 160.0"/>
+        <z type="uniform" parameters="0.0 160.0"/>
+      </space>
+      <angle type="monodirectional" reference_uvw="1.0 0.0 0.0"/>
+      <energy type="discrete">
+        <parameters>14100000.0 1.0</parameters>
+      </energy>
+    </source>
+    <survival_biasing>true</survival_biasing>
+    <weight_windows id="1">
+      <mesh>1</mesh>
+      <particle_type>neutron</particle_type>
+      <lower_ww_bounds>0.46135961568957096 0.2874485390202603 0.13256013950494605 0.052765209609807295 0.020958440832685638 0.006317250035749876 0.002627037175682506 0.00030032343592437284 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4611178493390162 0.28624862560842024 0.13999870622621136 0.05508479408959756 0.018281241958254993 0.0055577764872361555 0.0015265432226293397 0.00024298772352636966 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.46294957913063317 0.2857734367546051 0.13365623190336945 0.05034742166227103 0.017525851812913266 0.005096725451851077 0.0026297640951531403 0.00033732424392026144 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.45772598750472554 0.281494921471495 0.13604397962762246 0.054792881472295364 0.019802376898755525 0.0073351745579128495 0.002067392946066426 9.529474085926143e-05 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4739762983490318 0.28419061537046764 0.12757509901507888 0.0516920293019733 0.01919167874787235 0.007593035964707848 0.0017488176314107277 9.678267909681988e-05 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.47560199098558276 0.27728389146956994 0.12760802572535623 0.05251965811713552 0.022498960644951632 0.01063372459325151 0.004242071054914633 0.00045603112202665183 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.47659199471934693 0.28886666944252215 0.1258637573398161 0.05818862375955657 0.020476313720744762 0.007143193244018263 0.0022364083022515273 0.0003953123781408474 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4693487369606823 0.27180862139490125 0.12833455570423483 0.055146743559938344 0.020667403529470333 0.007891508723137146 0.001643551705407358 0.0006501416781353278 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4538724931023337 0.2824491421084296 0.1275341706351566 0.055027501141893705 0.02305114640508087 0.008599303158607198 0.0025082611194161804 0.000518530311231696 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.45258444753220123 0.26839102466484255 0.12991633918797083 0.05442263709947767 0.019695895223471486 0.005353204961887518 0.0015074698293840157 0.0001598680898180058 8.872047880811405e-05 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4482467985982804 0.2813276470183359 0.13449860790768647 0.056103278190533436 0.026274320334196962 0.006884071908429303 0.0033099390738735458 0.0005337454397674922 0.0001386380399465575 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4875748950139487 0.2908586705316248 0.14212060658392278 0.06068108009637272 0.019467970468789477 0.00637102427946399 0.0028510425266191687 0.0012184421778115488 0.00029404541567146187 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.5 0.2852101551297824 0.13622307172321643 0.058302519884339946 0.023124734915152625 0.007401527839638796 0.002527635652743992 0.0008509612315162482 0.00018213334574554768 7.815977984795461e-06 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.47706397688984176 0.28313436859495966 0.13170624744221976 0.0525453512766549 0.021111753158319105 0.0067451713955609645 0.003204270539718037 0.0010308107242263192 0.0002759210144794204 0.00013727805365387318 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.48641988659284513 0.2816173231471242 0.131541850061199 0.054793200248327956 0.016517701691156576 0.006757591781856257 0.0025425350750908644 0.0006383278085839443 2.279421641064226e-05 0.0003597432472224371 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4307755159245372 0.2652713784080849 0.12753857957535653 0.05470396852881577 0.02049817309420563 0.00566559741247352 0.0007213846765465147 6.848024591311009e-05 -1.0 8.609308814924014e-05 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.43631324024956025 0.2639077825530567 0.13368737962742414 0.05213531603720763 0.020628860469743833 0.008268384844678654 0.0028599221013934375 0.00013059757129982714 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.45926287238219 0.2635824148883888 0.13104280996799478 0.055379812186041905 0.019255042561941074 0.007252095690246872 0.0018026593488140996 0.0003215836458542421 9.14840176000331e-06 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4574378998400604 0.28714971179927723 0.1363507911051337 0.05010315954654347 0.017963278989571074 0.0058998176297971605 0.0021393135666168 0.00015677575033083482 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 0.4821442782978812 0.27704132233083506 0.14149074035662307 0.05546042815834048 0.016800649382269998 0.004096804603054233 0.0019161108398578026 0.0005289600253155307 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0 -1.0</lower_ww_bounds>
+      <upper_ww_bounds>2.306798078447855 1.4372426951013015 0.6628006975247303 0.2638260480490365 0.10479220416342819 0.03158625017874938 0.013135185878412529 0.0015016171796218643 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.3055892466950807 1.4312431280421012 0.6999935311310568 0.2754239704479878 0.09140620979127496 0.027788882436180776 0.007632716113146698 0.0012149386176318483 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.314747895653166 1.4288671837730256 0.6682811595168472 0.25173710831135515 0.08762925906456634 0.025483627259255386 0.013148820475765701 0.0016866212196013073 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.288629937523628 1.407474607357475 0.6802198981381123 0.2739644073614768 0.09901188449377762 0.036675872789564246 0.01033696473033213 0.00047647370429630714 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.369881491745159 1.4209530768523382 0.6378754950753944 0.2584601465098665 0.09595839373936176 0.03796517982353924 0.008744088157053638 0.00048391339548409945 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.3780099549279137 1.3864194573478497 0.6380401286267812 0.26259829058567763 0.11249480322475816 0.053168622966257545 0.021210355274573163 0.0022801556101332593 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.382959973596735 1.4443333472126108 0.6293187866990806 0.29094311879778284 0.10238156860372381 0.035715966220091315 0.011182041511257637 0.001976561890704237 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.3467436848034113 1.3590431069745064 0.6416727785211741 0.2757337177996917 0.10333701764735166 0.03945754361568573 0.00821775852703679 0.0032507083906766388 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.2693624655116684 1.412245710542148 0.637670853175783 0.27513750570946854 0.11525573202540434 0.04299651579303599 0.012541305597080901 0.00259265155615848 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.262922237661006 1.3419551233242126 0.6495816959398542 0.2721131854973884 0.09847947611735743 0.02676602480943759 0.007537349146920078 0.000799340449090029 0.0004436023940405703 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.2412339929914022 1.4066382350916795 0.6724930395384323 0.28051639095266717 0.1313716016709848 0.03442035954214652 0.016549695369367727 0.0026687271988374613 0.0006931901997327875 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.4378744750697434 1.4542933526581239 0.7106030329196139 0.3034054004818636 0.09733985234394739 0.03185512139731995 0.014255212633095843 0.006092210889057744 0.0014702270783573093 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.5 1.4260507756489118 0.6811153586160822 0.2915125994216997 0.11562367457576313 0.03700763919819398 0.012638178263719959 0.004254806157581241 0.0009106667287277384 3.9079889923977307e-05 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.385319884449209 1.4156718429747983 0.6585312372110987 0.2627267563832745 0.10555876579159552 0.03372585697780482 0.016021352698590185 0.005154053621131596 0.001379605072397102 0.000686390268269366 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.432099432964226 1.4080866157356209 0.657709250305995 0.2739660012416398 0.08258850845578287 0.03378795890928128 0.012712675375454322 0.0031916390429197216 0.0001139710820532113 0.0017987162361121855 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.1538775796226863 1.3263568920404245 0.6376928978767826 0.27351984264407886 0.10249086547102815 0.028327987062367603 0.0036069233827325737 0.0003424012295655504 -5.0 0.0004304654407462007 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.181566201247801 1.3195389127652835 0.6684368981371207 0.2606765801860381 0.10314430234871916 0.041341924223393264 0.014299610506967188 0.0006529878564991358 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.29631436191095 1.317912074441944 0.6552140498399739 0.27689906093020955 0.09627521280970537 0.03626047845123436 0.009013296744070498 0.0016079182292712106 4.574200880001655e-05 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.287189499200302 1.435748558996386 0.6817539555256685 0.25051579773271737 0.08981639494785537 0.029499088148985803 0.010696567833083998 0.0007838787516541741 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 2.410721391489406 1.3852066116541752 0.7074537017831153 0.2773021407917024 0.08400324691134999 0.020484023015271167 0.009580554199289014 0.0026448001265776534 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0 -5.0</upper_ww_bounds>
+      <survival_ratio>3.0</survival_ratio>
+      <max_split>10</max_split>
+      <weight_cutoff>1e-38</weight_cutoff>
+    </weight_windows>
+    <mesh id="1">
+      <dimension>20 20 1</dimension>
+      <lower_left>0.0 0.0 0.0</lower_left>
+      <upper_right>160.0 160.0 160.0</upper_right>
+    </mesh>
+    <weight_window_checkpoints>
+      <collision>true</collision>
+      <surface>true</surface>
+    </weight_window_checkpoints>
+  </settings>
+  <tallies>
+    <filter id="1" type="mesh">
+      <bins>1</bins>
+    </filter>
+    <tally id="1" name="flux">
+      <filters>1</filters>
+      <scores>flux</scores>
+    </tally>
+  </tallies>
+</model>
diff --git a/tests/regression_tests/weightwindows/survival_biasing/results_true.dat b/tests/regression_tests/weightwindows/survival_biasing/results_true.dat
new file mode 100644
index 000000000..b457a245c
--- /dev/null
+++ b/tests/regression_tests/weightwindows/survival_biasing/results_true.dat
@@ -0,0 +1 @@
+386e507008ed3c72c6e1a101aafc01cfaaff2c0b10555558d1eab6332441f7b17264b55002d721151bac2f3e7c1a8aac4c5ed243f5270533d171850f985206ed
\ No newline at end of file
diff --git a/tests/regression_tests/weightwindows/survival_biasing/test.py b/tests/regression_tests/weightwindows/survival_biasing/test.py
new file mode 100644
index 000000000..92604e338
--- /dev/null
+++ b/tests/regression_tests/weightwindows/survival_biasing/test.py
@@ -0,0 +1,81 @@
+import pytest
+import numpy as np
+
+import openmc
+from openmc.stats import Discrete, Point
+
+from tests.testing_harness import HashedPyAPITestHarness
+
+
+@pytest.fixture
+def model():
+    # Material
+    w = openmc.Material(name='Tungsten')
+    w.add_element('W', 1.0)
+    w.set_density('g/cm3', 19.25)
+
+    materials = openmc.Materials([w])
+
+    # Geometry surfaces
+    x0 = openmc.XPlane(x0=0.0, boundary_type='reflective')
+    x1 = openmc.XPlane(x0=160.0, boundary_type='vacuum')
+    y0 = openmc.YPlane(y0=0.0, boundary_type='reflective')
+    y1 = openmc.YPlane(y0=160.0, boundary_type='reflective')
+    z0 = openmc.ZPlane(z0=0.0, boundary_type='reflective')
+    z1 = openmc.ZPlane(z0=160.0, boundary_type='reflective')
+
+    region = +x0 & -x1 & +y0 & -y1 & +z0 & -z1
+    cell = openmc.Cell(region=region, fill=w)
+    root = openmc.Universe(cells=[cell])
+    geometry = openmc.Geometry(root)
+
+    # Source: planar on x=0, mono-directional along +x, 14.1 MeV neutrons
+    space = openmc.stats.CartesianIndependent(
+        openmc.stats.Discrete([0.01], [1.0]),
+        openmc.stats.Uniform(0.0, 160.0),
+        openmc.stats.Uniform(0.0, 160.0),
+    )
+    angle = openmc.stats.Monodirectional((1.0, 0.0, 0.0))
+    energy = openmc.stats.Discrete([14.1e6], [1.0])
+
+    source = openmc.Source(space=space, angle=angle, energy=energy)
+
+    settings = openmc.Settings()
+    settings.run_mode = 'fixed source'
+    settings.batches = 5
+    settings.particles = 50
+    settings.source = source
+
+    model = openmc.Model(geometry=geometry, materials=materials, settings=settings)
+
+    # Mesh tally: 1 cm voxels, flux only
+    mesh = openmc.RegularMesh()
+    mesh.dimension = (20, 20, 1)
+    mesh.lower_left = (0.0, 0.0, 0.0)
+    mesh.upper_right = (160.0, 160.0, 160.0)
+
+    mesh_filter = openmc.MeshFilter(mesh)
+    flux_tally = openmc.Tally(name='flux')
+    flux_tally.filters = [mesh_filter]
+    flux_tally.scores = ['flux']
+    tallies = openmc.Tallies([flux_tally])
+    model.tallies = tallies
+
+    lower_ww_bounds = np.loadtxt('ww_n.txt')
+
+    weight_windows = openmc.WeightWindows(mesh,
+                                          lower_ww_bounds,
+                                          upper_bound_ratio=5.0,
+                                          particle_type='neutron')
+
+    model.settings.weight_windows = weight_windows
+    model.settings.weight_window_checkpoints = {'surface': True,
+                                                'collision': True}
+    model.settings.survival_biasing = True
+
+    return model
+
+
+def test_weight_windows_with_survival_biasing(model):
+    harness = HashedPyAPITestHarness('statepoint.5.h5', model)
+    harness.main()
diff --git a/tests/regression_tests/weightwindows/survival_biasing/ww_n.txt b/tests/regression_tests/weightwindows/survival_biasing/ww_n.txt
new file mode 100644
index 000000000..aea1ff132
--- /dev/null
+++ b/tests/regression_tests/weightwindows/survival_biasing/ww_n.txt
@@ -0,0 +1,400 @@
+4.613596156895709566e-01
+4.611178493390161726e-01
+4.629495791306331709e-01
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+5.000000000000000000e-01
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+4.363132402495602524e-01
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