diff --git a/src/lagrangian/dsmc/submodels/InflowBoundaryModel/FreeStream/FreeStream.C b/src/lagrangian/dsmc/submodels/InflowBoundaryModel/FreeStream/FreeStream.C
index 58526a048a..cd18d9064d 100644
--- a/src/lagrangian/dsmc/submodels/InflowBoundaryModel/FreeStream/FreeStream.C
+++ b/src/lagrangian/dsmc/submodels/InflowBoundaryModel/FreeStream/FreeStream.C
@@ -249,9 +249,16 @@ void Foam::FreeStream<CloudType>::inflow()
             {
                 scalar& faceAccumulator = pFA[i][f];
 
-                // Number of particles to insert
+                // Number of whole particles to insert
                 label nI = max(label(faceAccumulator), 0);
 
+                // Add another particle with a probability proportional to the
+                // remainder of taking the integer part of faceAccumulator
+                if ((faceAccumulator - nI) > rndGen.scalar01())
+                {
+                    nI++;
+                }
+
                 faceAccumulator -= nI;
 
                 label typeId = moleculeTypeIds_[i];