diff --git a/.gitignore b/.gitignore
index 1b5be302..f150b66e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -23,3 +23,6 @@ Custom_scripts/
 Data_Files/MicroscopyCalibration/Files/
 .pytest_cache/
 .python-version
+
+# PyCharm metadata
+.idea/
diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 620f13e6..2a1ca15a 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -6,6 +6,11 @@ Submit4DN
 Change Log
 ----------
 
+3.1.1
+=====
+
+* Bug fix: some "empty" cells were not handled correctly.
+
 3.1.0
 =====
 
diff --git a/pyproject.toml b/pyproject.toml
index fa26981e..7fbd1e56 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "Submit4DN"
-version = "3.1.0"
+version = "3.1.1"
 description = "Utility package for submitting data to the 4DN Data Portal"
 authors = ["4DN-DCIC Team <support@4dnucleome.org>"]
 license = "MIT"
diff --git a/wranglertools/import_data.py b/wranglertools/import_data.py
index ee2f83e3..8b0b21fd 100755
--- a/wranglertools/import_data.py
+++ b/wranglertools/import_data.py
@@ -285,6 +285,8 @@ def cell_value(cell):
     value = cell.value
     if ctype == openpyxl.cell.cell.TYPE_ERROR:  # pragma: no cover
         raise ValueError('Cell %s contains a cell error' % str(cell.coordinate))
+    elif value is None:
+        return ''
     elif ctype == openpyxl.cell.cell.TYPE_BOOL:
         boolstr = str(value).strip()
         if boolstr == 'TRUE':