diff --git a/ApplicationCode/ProjectDataModel/RimEclipseCase.cpp b/ApplicationCode/ProjectDataModel/RimEclipseCase.cpp
index 8a9796cb5e..a2c032bada 100644
--- a/ApplicationCode/ProjectDataModel/RimEclipseCase.cpp
+++ b/ApplicationCode/ProjectDataModel/RimEclipseCase.cpp
@@ -608,8 +608,12 @@ void RimEclipseCase::computeCachedData()
 
         {
             auto task = pInf.task( "Calculating faults", 17 );
-            rigEclipseCase->mainGrid()->calculateFaults(
-                rigEclipseCase->activeCellInfo( RiaDefines::PorosityModelType::MATRIX_MODEL ) );
+
+            bool computeNncs = RiaApplication::instance()->preferences()->readerSettings()->importNNCs();
+
+            rigEclipseCase->mainGrid()->calculateFaults( rigEclipseCase->activeCellInfo(
+                                                             RiaDefines::PorosityModelType::MATRIX_MODEL ),
+                                                         computeNncs );
         }
 
         {
diff --git a/ApplicationCode/ProjectDataModel/RimEclipseCaseCollection.cpp b/ApplicationCode/ProjectDataModel/RimEclipseCaseCollection.cpp
index d13ab58180..ec3c386141 100644
--- a/ApplicationCode/ProjectDataModel/RimEclipseCaseCollection.cpp
+++ b/ApplicationCode/ProjectDataModel/RimEclipseCaseCollection.cpp
@@ -20,6 +20,11 @@
 
 #include "RimEclipseCaseCollection.h"
 
+#include "RiaApplication.h"
+#include "RiaPreferences.h"
+
+#include "RifReaderSettings.h"
+
 #include "RigEclipseCaseData.h"
 #include "RigGridManager.h"
 #include "RigMainGrid.h"
@@ -127,8 +132,11 @@ RigMainGrid* RimEclipseCaseCollection::registerCaseInGridCollection( RigEclipseC
         // This is the first insertion of this grid, compute cached data
         rigEclipseCase->mainGrid()->computeCachedData();
 
-        rigEclipseCase->mainGrid()->calculateFaults(
-            rigEclipseCase->activeCellInfo( RiaDefines::PorosityModelType::MATRIX_MODEL ) );
+        bool computeNncs = RiaApplication::instance()->preferences()->readerSettings()->importNNCs();
+
+        rigEclipseCase->mainGrid()->calculateFaults( rigEclipseCase->activeCellInfo(
+                                                         RiaDefines::PorosityModelType::MATRIX_MODEL ),
+                                                     computeNncs );
 
         equalGrid = rigEclipseCase->mainGrid();
     }
diff --git a/ApplicationCode/ReservoirDataModel/RigCaseCellResultsData.cpp b/ApplicationCode/ReservoirDataModel/RigCaseCellResultsData.cpp
index 8998170921..fc5fa837b5 100644
--- a/ApplicationCode/ReservoirDataModel/RigCaseCellResultsData.cpp
+++ b/ApplicationCode/ReservoirDataModel/RigCaseCellResultsData.cpp
@@ -3091,6 +3091,13 @@ void RigCaseCellResultsData::computeAllanResults( RigCaseCellResultsData* cellRe
     if ( cellResultsData && cellResultsData->activeFormationNames() &&
          !cellResultsData->activeFormationNames()->formationNames().empty() )
     {
+        // If import of NNC is disabled in preferences, we must make ensure that computed NNC connections are in place
+        if ( mainGrid->nncData()->nativeConnectionCount() == mainGrid->nncData()->connections().size() )
+        {
+            mainGrid->nncData()->computeCompleteSetOfNncs( mainGrid, cellResultsData->activeCellInfo() );
+            mainGrid->distributeNNCsToFaults();
+        }
+
         auto fnNamesResAddr = RigEclipseResultAddress( RiaDefines::ResultCatType::FORMATION_NAMES,
                                                        RiaDefines::activeFormationNamesResultName() );
         auto fnAllanResultResAddr =
diff --git a/ApplicationCode/ReservoirDataModel/RigMainGrid.cpp b/ApplicationCode/ReservoirDataModel/RigMainGrid.cpp
index 25b5dc2703..02334612b5 100644
--- a/ApplicationCode/ReservoirDataModel/RigMainGrid.cpp
+++ b/ApplicationCode/ReservoirDataModel/RigMainGrid.cpp
@@ -413,7 +413,7 @@ bool RigMainGrid::hasFaultWithName( const QString& name ) const
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
-void RigMainGrid::calculateFaults( const RigActiveCellInfo* activeCellInfo )
+void RigMainGrid::calculateFaults( const RigActiveCellInfo* activeCellInfo, bool computeNncs )
 {
     if ( hasFaultWithName( RiaDefines::undefinedGridFaultName() ) &&
          hasFaultWithName( RiaDefines::undefinedGridFaultWithInactiveName() ) )
@@ -556,7 +556,10 @@ void RigMainGrid::calculateFaults( const RigActiveCellInfo* activeCellInfo )
         }
     }
 
-    this->nncData()->computeCompleteSetOfNncs( this, activeCellInfo );
+    if ( computeNncs )
+    {
+        this->nncData()->computeCompleteSetOfNncs( this, activeCellInfo );
+    }
 
     distributeNNCsToFaults();
 }
diff --git a/ApplicationCode/ReservoirDataModel/RigMainGrid.h b/ApplicationCode/ReservoirDataModel/RigMainGrid.h
index 033f3d8fef..37742688a2 100644
--- a/ApplicationCode/ReservoirDataModel/RigMainGrid.h
+++ b/ApplicationCode/ReservoirDataModel/RigMainGrid.h
@@ -70,7 +70,7 @@ public:
     void                             setFaults( const cvf::Collection<RigFault>& faults );
     const cvf::Collection<RigFault>& faults() const;
     cvf::Collection<RigFault>&       faults();
-    void                             calculateFaults( const RigActiveCellInfo* activeCellInfo );
+    void                             calculateFaults( const RigActiveCellInfo* activeCellInfo, bool computeNncs );
 
     void distributeNNCsToFaults();