diff --git a/README.md b/README.md
index 1fd80acc..cd6e7bd8 100644
--- a/README.md
+++ b/README.md
@@ -48,6 +48,9 @@ All notable changes to this project will be documented in this file. The format
 
 ## [Unreleased]
 
+### Fixed
+- Fix `tovoigt()` helper for data with more or less than two trailing axes.
+
 ## [3.1.0] - 2022-05-02
 
 ### Added
diff --git a/felupe/math/_tensor.py b/felupe/math/_tensor.py
index 1d68cc7f..2c049bba 100644
--- a/felupe/math/_tensor.py
+++ b/felupe/math/_tensor.py
@@ -279,8 +279,8 @@ def ddot(A, B, n=2, parallel=False):
 
 def tovoigt(A):
     "Convert (3, 3) tensor to (6, ) voigt notation."
-    B = np.zeros((6, *A.shape[-2:]))
+    B = np.zeros((6, *A.shape[2:]))
     ij = [(0, 0), (1, 1), (2, 2), (0, 1), (1, 2), (0, 2)]
     for i6, (i, j) in enumerate(ij):
-        B[i6, :, :] = A[i, j, :, :]
+        B[i6] = A[i, j]
     return B