diff --git a/tests/regression_tests/cmfd_feed_expanding_window/__init__.py b/tests/regression_tests/cmfd_feed_expanding_window/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/geometry.xml b/tests/regression_tests/cmfd_feed_expanding_window/geometry.xml
new file mode 100644
index 000000000..73ea679c4
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/geometry.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<geometry>
+
+<!-- Definition of Cells -->
+  <cell id="1">
+    <universe>0</universe>
+    <region>-1 2 -3 4 -5 6</region>
+    <material>1</material>
+  </cell>
+
+<!-- Defition of Surfaces -->
+  <surface id="1">
+    <type>x-plane</type>
+    <coeffs>10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="2">
+    <type>x-plane</type>
+    <coeffs>-10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="3">
+    <type>y-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="4">
+    <type>y-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="5">
+    <type>z-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="6">
+    <type>z-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/materials.xml b/tests/regression_tests/cmfd_feed_expanding_window/materials.xml
new file mode 100644
index 000000000..70580e3a8
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/materials.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materials>
+
+  <!-- Definition of materials -->
+  <material id="1">
+    <density value="19" units="g/cc" />
+    <nuclide name="U235" wo="0.21" />
+    <nuclide name="U238" wo="0.68" />
+    <nuclide name="O16" wo="0.11" />
+  </material>
+
+</materials>
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/results_true.dat b/tests/regression_tests/cmfd_feed_expanding_window/results_true.dat
new file mode 100644
index 000000000..b67bef0f7
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/results_true.dat
@@ -0,0 +1,488 @@
+k-combined:
+1.165403E+00 1.129918E-02
+tally 1:
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+tally 2:
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+tally 3:
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+tally 4:
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+tally 5:
+7.459301E-01
+5.564117E-01
+1.149820E-01
+1.322085E-02
+1.356702E+00
+1.840641E+00
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+4.708836E-02
+7.994935E-01
+6.391898E-01
+1.002481E-01
+1.004969E-02
+cmfd indices
+1.000000E+01
+1.000000E+00
+1.000000E+00
+1.000000E+00
+k cmfd
+1.143597E+00
+1.163387E+00
+1.173384E+00
+1.171035E+00
+1.147196E+00
+1.122260E+00
+1.106380E+00
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+1.142380E+00
+1.132168E+00
+1.132560E+00
+1.153781E+00
+1.170308E+00
+1.184540E+00
+cmfd entropy
+3.212002E+00
+3.206393E+00
+3.223984E+00
+3.222764E+00
+3.232123E+00
+3.242083E+00
+3.246067E+00
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+3.236922E+00
+3.229545E+00
+3.225232E+00
+3.221485E+00
+3.219108E+00
+cmfd balance
+8.26180E-03
+4.27338E-03
+2.22686E-03
+1.93026E-03
+1.96979E-03
+2.13756E-03
+2.01479E-03
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+1.48370E-03
+1.75963E-03
+1.98194E-03
+1.87306E-03
+1.24780E-03
+1.15560E-03
+cmfd dominance ratio
+5.404E-01
+5.406E-01
+5.449E-01
+5.473E-01
+5.534E-01
+5.623E-01
+5.738E-01
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+5.569E-01
+5.556E-01
+5.555E-01
+5.583E-01
+5.544E-01
+5.486E-01
+5.412E-01
+5.383E-01
+cmfd openmc source comparison
+1.575499E-02
+1.293688E-02
+3.531746E-03
+8.281178E-03
+5.771681E-03
+7.459013E-03
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+8.839928E-03
+5.456904E-03
+5.668412E-03
+4.016377E-03
+4.179381E-03
+cmfd source
+4.116210E-02
+7.797480E-02
+1.062822E-01
+1.333719E-01
+1.481091E-01
+1.370422E-01
+1.299765E-01
+9.887040E-02
+8.228753E-02
+4.492330E-02
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/settings.xml b/tests/regression_tests/cmfd_feed_expanding_window/settings.xml
new file mode 100644
index 000000000..24b0b6ab5
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/settings.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source>
+    <space>
+      <type>box</type>
+      <parameters>-10 -1 -1 10 1 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 10 1 1 </dimension>
+    <lower_left> -10.0 -1.0 -1.0 </lower_left>
+    <upper_right> 10.0  1.0  1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+</settings>
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/tallies.xml b/tests/regression_tests/cmfd_feed_expanding_window/tallies.xml
new file mode 100644
index 000000000..c86971114
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-10 -1 -1 </lower_left>
+    <upper_right>10 1 1</upper_right>
+    <dimension>10 1 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_feed_expanding_window/test.py b/tests/regression_tests/cmfd_feed_expanding_window/test.py
new file mode 100644
index 000000000..9a2697dff
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_expanding_window/test.py
@@ -0,0 +1,26 @@
+from tests.testing_harness import CMFDTestHarness
+from openmc import cmfd
+
+
+def test_cmfd_feed_rolling_window():
+    """Test 1 group CMFD solver with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = cmfd.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = cmfd.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.tally_begin = 5
+    cmfd_run.feedback_begin = 10
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.window_type = 'expanding'
+    cmfd_run.run()
+
+    # Initialize and run CMFD test harness
+    harness = CMFDTestHarness('statepoint.20.h5', cmfd_run)
+    harness.main()
diff --git a/tests/regression_tests/cmfd_feed_ref_d/__init__.py b/tests/regression_tests/cmfd_feed_ref_d/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/regression_tests/cmfd_feed_ref_d/geometry.xml b/tests/regression_tests/cmfd_feed_ref_d/geometry.xml
new file mode 100644
index 000000000..73ea679c4
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/geometry.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<geometry>
+
+<!-- Definition of Cells -->
+  <cell id="1">
+    <universe>0</universe>
+    <region>-1 2 -3 4 -5 6</region>
+    <material>1</material>
+  </cell>
+
+<!-- Defition of Surfaces -->
+  <surface id="1">
+    <type>x-plane</type>
+    <coeffs>10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="2">
+    <type>x-plane</type>
+    <coeffs>-10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="3">
+    <type>y-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="4">
+    <type>y-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="5">
+    <type>z-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="6">
+    <type>z-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_feed_ref_d/materials.xml b/tests/regression_tests/cmfd_feed_ref_d/materials.xml
new file mode 100644
index 000000000..70580e3a8
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/materials.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materials>
+
+  <!-- Definition of materials -->
+  <material id="1">
+    <density value="19" units="g/cc" />
+    <nuclide name="U235" wo="0.21" />
+    <nuclide name="U238" wo="0.68" />
+    <nuclide name="O16" wo="0.11" />
+  </material>
+
+</materials>
diff --git a/tests/regression_tests/cmfd_feed_ref_d/results_true.dat b/tests/regression_tests/cmfd_feed_ref_d/results_true.dat
new file mode 100644
index 000000000..06440d81f
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/results_true.dat
@@ -0,0 +1,488 @@
+k-combined:
+1.165408E+00 1.127320E-02
+tally 1:
+1.141009E+01
+1.305436E+01
+2.074878E+01
+4.311543E+01
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diff --git a/tests/regression_tests/cmfd_feed_ref_d/settings.xml b/tests/regression_tests/cmfd_feed_ref_d/settings.xml
new file mode 100644
index 000000000..24b0b6ab5
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/settings.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source>
+    <space>
+      <type>box</type>
+      <parameters>-10 -1 -1 10 1 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 10 1 1 </dimension>
+    <lower_left> -10.0 -1.0 -1.0 </lower_left>
+    <upper_right> 10.0  1.0  1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+</settings>
diff --git a/tests/regression_tests/cmfd_feed_ref_d/tallies.xml b/tests/regression_tests/cmfd_feed_ref_d/tallies.xml
new file mode 100644
index 000000000..c86971114
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-10 -1 -1 </lower_left>
+    <upper_right>10 1 1</upper_right>
+    <dimension>10 1 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_feed_ref_d/test.py b/tests/regression_tests/cmfd_feed_ref_d/test.py
new file mode 100644
index 000000000..4facabb5f
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_ref_d/test.py
@@ -0,0 +1,27 @@
+from tests.testing_harness import CMFDTestHarness
+from openmc import cmfd
+
+
+def test_cmfd_feed_rolling_window():
+    """Test 1 group CMFD solver with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = cmfd.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = cmfd.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.tally_begin = 5
+    cmfd_run.feedback_begin = 10
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.window_type = 'expanding'
+    cmfd_run.ref_d = [0.542]
+    cmfd_run.run()
+
+    # Initialize and run CMFD test harness
+    harness = CMFDTestHarness('statepoint.20.h5', cmfd_run)
+    harness.main()
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/__init__.py b/tests/regression_tests/cmfd_feed_rolling_window/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/geometry.xml b/tests/regression_tests/cmfd_feed_rolling_window/geometry.xml
new file mode 100644
index 000000000..73ea679c4
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/geometry.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<geometry>
+
+<!-- Definition of Cells -->
+  <cell id="1">
+    <universe>0</universe>
+    <region>-1 2 -3 4 -5 6</region>
+    <material>1</material>
+  </cell>
+
+<!-- Defition of Surfaces -->
+  <surface id="1">
+    <type>x-plane</type>
+    <coeffs>10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="2">
+    <type>x-plane</type>
+    <coeffs>-10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="3">
+    <type>y-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="4">
+    <type>y-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="5">
+    <type>z-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="6">
+    <type>z-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/materials.xml b/tests/regression_tests/cmfd_feed_rolling_window/materials.xml
new file mode 100644
index 000000000..70580e3a8
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/materials.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materials>
+
+  <!-- Definition of materials -->
+  <material id="1">
+    <density value="19" units="g/cc" />
+    <nuclide name="U235" wo="0.21" />
+    <nuclide name="U238" wo="0.68" />
+    <nuclide name="O16" wo="0.11" />
+  </material>
+
+</materials>
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/results_true.dat b/tests/regression_tests/cmfd_feed_rolling_window/results_true.dat
new file mode 100644
index 000000000..518052683
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/results_true.dat
@@ -0,0 +1,488 @@
+k-combined:
+1.172120E+00 9.761693E-03
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diff --git a/tests/regression_tests/cmfd_feed_rolling_window/settings.xml b/tests/regression_tests/cmfd_feed_rolling_window/settings.xml
new file mode 100644
index 000000000..24b0b6ab5
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/settings.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source>
+    <space>
+      <type>box</type>
+      <parameters>-10 -1 -1 10 1 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 10 1 1 </dimension>
+    <lower_left> -10.0 -1.0 -1.0 </lower_left>
+    <upper_right> 10.0  1.0  1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+</settings>
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/tallies.xml b/tests/regression_tests/cmfd_feed_rolling_window/tallies.xml
new file mode 100644
index 000000000..c86971114
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-10 -1 -1 </lower_left>
+    <upper_right>10 1 1</upper_right>
+    <dimension>10 1 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_feed_rolling_window/test.py b/tests/regression_tests/cmfd_feed_rolling_window/test.py
new file mode 100644
index 000000000..67861be4a
--- /dev/null
+++ b/tests/regression_tests/cmfd_feed_rolling_window/test.py
@@ -0,0 +1,27 @@
+from tests.testing_harness import CMFDTestHarness
+from openmc import cmfd
+
+
+def test_cmfd_feed_rolling_window():
+    """Test 1 group CMFD solver with CMFD feedback"""
+    # Initialize and set CMFD mesh
+    cmfd_mesh = cmfd.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+
+    # Initialize and run CMFDRun object
+    cmfd_run = cmfd.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.tally_begin = 5
+    cmfd_run.feedback_begin = 10
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.window_type = 'rolling'
+    cmfd_run.window_size = 5
+    cmfd_run.run()
+
+    # Initialize and run CMFD test harness
+    harness = CMFDTestHarness('statepoint.20.h5', cmfd_run)
+    harness.main()
diff --git a/tests/regression_tests/cmfd_restart/__init__.py b/tests/regression_tests/cmfd_restart/__init__.py
new file mode 100644
index 000000000..e69de29bb
diff --git a/tests/regression_tests/cmfd_restart/geometry.xml b/tests/regression_tests/cmfd_restart/geometry.xml
new file mode 100644
index 000000000..73ea679c4
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/geometry.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<geometry>
+
+<!-- Definition of Cells -->
+  <cell id="1">
+    <universe>0</universe>
+    <region>-1 2 -3 4 -5 6</region>
+    <material>1</material>
+  </cell>
+
+<!-- Defition of Surfaces -->
+  <surface id="1">
+    <type>x-plane</type>
+    <coeffs>10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="2">
+    <type>x-plane</type>
+    <coeffs>-10</coeffs>
+    <boundary> vacuum </boundary>
+  </surface>
+  <surface id="3">
+    <type>y-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="4">
+    <type>y-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="5">
+    <type>z-plane</type>
+    <coeffs>1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+  <surface id="6">
+    <type>z-plane</type>
+    <coeffs>-1</coeffs>
+    <boundary>reflective</boundary>
+  </surface>
+
+</geometry>
diff --git a/tests/regression_tests/cmfd_restart/materials.xml b/tests/regression_tests/cmfd_restart/materials.xml
new file mode 100644
index 000000000..70580e3a8
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/materials.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0"?>
+<materials>
+
+  <!-- Definition of materials -->
+  <material id="1">
+    <density value="19" units="g/cc" />
+    <nuclide name="U235" wo="0.21" />
+    <nuclide name="U238" wo="0.68" />
+    <nuclide name="O16" wo="0.11" />
+  </material>
+
+</materials>
diff --git a/tests/regression_tests/cmfd_restart/results_true.dat b/tests/regression_tests/cmfd_restart/results_true.dat
new file mode 100644
index 000000000..4a2c6eea2
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/results_true.dat
@@ -0,0 +1,488 @@
+k-combined:
+1.169891E+00 6.289489E-03
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+4.093396E-01
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+tally 5:
+1.538652E+01
+1.196332E+01
+2.252427E+00
+2.605738E-01
+2.911344E+01
+4.267319E+01
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+3.818076E+00
+7.509442E-01
+1.574994E+01
+1.248291E+01
+2.219928E+00
+2.515492E-01
+cmfd indices
+1.000000E+01
+1.000000E+00
+1.000000E+00
+1.000000E+00
+k cmfd
+1.170416E+00
+1.172966E+00
+1.165537E+00
+1.170979E+00
+1.161922E+00
+1.157523E+00
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+1.170570E+00
+1.168115E+00
+1.174081E+00
+1.169458E+00
+1.167848E+00
+1.165116E+00
+cmfd entropy
+3.203643E+00
+3.207943E+00
+3.213367E+00
+3.214360E+00
+3.219634E+00
+3.222232E+00
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+3.230728E+00
+3.231662E+00
+3.233316E+00
+3.233193E+00
+3.232564E+00
+cmfd balance
+4.00906E-03
+4.43177E-03
+3.15267E-03
+3.51038E-03
+2.05209E-03
+2.06865E-03
+1.50243E-03
+1.58983E-03
+1.56602E-03
+1.17001E-03
+9.50759E-04
+9.07259E-04
+1.00900E-03
+1.06470E-03
+1.16361E-03
+9.75631E-04
+cmfd dominance ratio
+5.397E-01
+5.425E-01
+5.481E-01
+5.473E-01
+5.503E-01
+5.502E-01
+5.483E-01
+5.520E-01
+5.505E-01
+3.216E-01
+5.373E-01
+5.517E-01
+5.508E-01
+5.524E-01
+5.524E-01
+5.523E-01
+cmfd openmc source comparison
+6.959834E-03
+5.655657E-03
+3.886186E-03
+4.035116E-03
+3.043277E-03
+5.455474E-03
+4.515310E-03
+2.439840E-03
+2.114032E-03
+2.673132E-03
+2.431749E-03
+4.330928E-03
+3.404647E-03
+3.680298E-03
+3.309620E-03
+3.705541E-03
+cmfd source
+4.697085E-02
+7.920706E-02
+1.107968E-01
+1.250932E-01
+1.383930E-01
+1.380648E-01
+1.246874E-01
+1.113705E-01
+8.203754E-02
+4.337882E-02
diff --git a/tests/regression_tests/cmfd_restart/settings.xml b/tests/regression_tests/cmfd_restart/settings.xml
new file mode 100644
index 000000000..ba5495911
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/settings.xml
@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<settings>
+
+  <!-- Parameters for criticality calculation -->
+  <run_mode>eigenvalue</run_mode>
+  <batches>20</batches>
+  <inactive>10</inactive>
+  <particles>1000</particles>
+
+  <!-- Starting source -->
+  <source>
+    <space>
+      <type>box</type>
+      <parameters>-10 -1 -1 10 1 1</parameters>
+    </space>
+  </source>
+
+  <!-- Shannon Entropy -->
+  <mesh id="10">
+    <dimension> 10 1 1 </dimension>
+    <lower_left> -10.0 -1.0 -1.0 </lower_left>
+    <upper_right> 10.0  1.0  1.0 </upper_right>
+  </mesh>
+  <entropy_mesh>10</entropy_mesh>
+
+  <state_point batches="15 20" />
+
+</settings>
diff --git a/tests/regression_tests/cmfd_restart/tallies.xml b/tests/regression_tests/cmfd_restart/tallies.xml
new file mode 100644
index 000000000..c86971114
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/tallies.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<tallies>
+
+  <mesh id="1">
+    <type>regular</type>
+    <lower_left>-10 -1 -1 </lower_left>
+    <upper_right>10 1 1</upper_right>
+    <dimension>10 1 1</dimension>
+  </mesh>
+
+  <filter id="1">
+    <type>mesh</type>
+    <bins>1</bins>
+  </filter>
+
+  <tally id="1">
+    <filters>1</filters>
+    <scores>flux</scores>
+  </tally>
+
+</tallies>
diff --git a/tests/regression_tests/cmfd_restart/test.py b/tests/regression_tests/cmfd_restart/test.py
new file mode 100644
index 000000000..6f89947f3
--- /dev/null
+++ b/tests/regression_tests/cmfd_restart/test.py
@@ -0,0 +1,72 @@
+import glob
+import os
+import copy
+
+from tests.testing_harness import CMFDTestHarness
+from openmc import cmfd
+import numpy as np
+
+
+class CMFDRestartTestHarness(CMFDTestHarness):
+    def __init__(self, final_sp, restart_sp, cmfd_run1, cmfd_run2):
+        super().__init__(final_sp, cmfd_run1)
+        self._cmfd_restart_run = cmfd_run2
+        self._restart_sp = restart_sp
+
+    def execute_test(self):
+        try:
+            # Compare results from first CMFD run
+            self._test_output_created()
+            results = self._get_results()
+            results += self._cmfdrun_results
+            self._write_results(results)
+            self._compare_results()
+
+            # Run CMFD from restart file
+            statepoint = glob.glob(os.path.join(os.getcwd(), self._restart_sp))
+            assert len(statepoint) == 1
+            statepoint = statepoint[0]
+            self._cmfd_restart_run.run(args=['-r', statepoint])
+
+            # Compare results from second CMFD run
+            self._test_output_created()
+            self._create_cmfd_result_str(self._cmfd_restart_run)
+            results = self._get_results()
+            results += self._cmfdrun_results
+            self._write_results(results)
+            self._compare_results()
+        finally:
+            self._cleanup()
+
+
+def test_cmfd_restart():
+    """Test 1 group CMFD solver with restart run"""
+    # Initialize and set CMFD mesh, create a copy for second run
+    cmfd_mesh = cmfd.CMFDMesh()
+    cmfd_mesh.lower_left = -10.0, -1.0, -1.0
+    cmfd_mesh.upper_right = 10.0, 1.0, 1.0
+    cmfd_mesh.dimension = 10, 1, 1
+    cmfd_mesh.albedo = 0.0, 0.0, 1.0, 1.0, 1.0, 1.0
+    cmfd_mesh2 = copy.deepcopy(cmfd_mesh)
+
+    # Initialize and run first CMFDRun object
+    cmfd_run = cmfd.CMFDRun()
+    cmfd_run.mesh = cmfd_mesh
+    cmfd_run.tally_begin = 5
+    cmfd_run.feedback_begin = 5
+    cmfd_run.feedback = True
+    cmfd_run.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+    cmfd_run.run()
+
+    # Initialize second CMFDRun object which will be run from restart file
+    cmfd_run2 = cmfd.CMFDRun()
+    cmfd_run2.mesh = cmfd_mesh2
+    cmfd_run2.tally_begin = 5
+    cmfd_run2.feedback_begin = 5
+    cmfd_run2.feedback = True
+    cmfd_run2.gauss_seidel_tolerance = [1.e-15, 1.e-20]
+
+    # Initialize and run CMFD restart test harness
+    harness = CMFDRestartTestHarness('statepoint.20.h5', 'statepoint.15.h5',
+                                     cmfd_run, cmfd_run2)
+    harness.main()