diff --git a/samplesheetutils/utils/a3m.py b/samplesheetutils/utils/a3m.py
index 227a48b..e590f49 100644
--- a/samplesheetutils/utils/a3m.py
+++ b/samplesheetutils/utils/a3m.py
@@ -47,6 +47,6 @@ def make_a3m(fp, sample: Union[Alignment, list], header='>', fixed_width=False,
         sample_data = si.data
         if fixed_width:
             sample_data = '\n'.join([sample_data[i:i+fixed_width_column_count] for i in range(0, len(sample_data), fixed_width_column_count)]) 
-        fp.write(f"{header}{si.name}\n{sample_data}")
+        fp.write(f"{header}{si.name}\n{sample_data}\n")
         fp.flush()