diff --git a/tests/test_importers.py b/tests/test_importers.py
index 5c63d71930ed4ff95f4666d8b7546d9be3df3952..bb8757c9c33b65b7a1d8a4d6acd77205465e8fd1 100644
--- a/tests/test_importers.py
+++ b/tests/test_importers.py
@@ -1,8 +1,11 @@
+import csv
 import datetime
 import decimal
+import io
 import importlib
 import itertools
 import pathlib
+import shutil
 import re
 
 import pytest
@@ -28,6 +31,25 @@ class TestImporters:
         with source_path.open() as source_file:
             assert importer.can_import(source_file)
 
+    @pytest.mark.parametrize('source_path,importer,header_rows,header_cols', [
+        (t['source'], t['importer'], t['header_rows'], t['header_cols'])
+        for t in test_data if t.get('header_rows')
+    ])
+    def test_can_import_squared_csv(self, source_path, importer, header_rows, header_cols):
+        # Sometimes when we munge spreadsheets by hand (e.g., to filter by
+        # project) tools like LibreOffice Calc write a "squared" spreadsheet,
+        # where every row has the same length.  This test ensures the results
+        # are still recognized for import.
+        with io.StringIO() as squared_file:
+            csv_writer = csv.writer(squared_file)
+            with source_path.open() as source_file:
+                for row in itertools.islice(csv.reader(source_file), header_rows):
+                    padding = [None] * (header_cols - len(row))
+                    csv_writer.writerow(row + padding)
+                shutil.copyfileobj(source_file, squared_file)
+            squared_file.seek(0)
+            assert importer.can_import(squared_file)
+
     @pytest.mark.parametrize('source_path,import_class,expect_results', [
         (t['source'], t['importer'], t['expect']) for t in test_data
     ])