diff --git a/src/storm/storage/SparseMatrix.cpp b/src/storm/storage/SparseMatrix.cpp
index 360e68ee8..ecf29de4a 100644
--- a/src/storm/storage/SparseMatrix.cpp
+++ b/src/storm/storage/SparseMatrix.cpp
@@ -1205,7 +1205,9 @@ namespace storm {
             }
             // Finally create matrix and return result.
             auto result = matrixBuilder.build();
-            result.setRowGroupIndices(this->rowGroupIndices.get());
+            if (this->rowGroupIndices) {
+                result.setRowGroupIndices(this->rowGroupIndices.get());
+            }
             return result;
         }