diff --git a/src/Csv.php b/src/Csv.php
index a9a4841..98b21e9 100644
--- a/src/Csv.php
+++ b/src/Csv.php
@@ -1261,7 +1261,7 @@ class Csv {
                 }
             }
 
-            if ($equal) {
+            if ($equal || $depth === 1) {
                 $match = $almost ? 2 : 1;
                 $pref = strpos($preferred, $char);
                 $pref = ($pref !== false) ? str_pad($pref, 3, '0', STR_PAD_LEFT) : '999';
diff --git a/tests/example_files/single_row.csv b/tests/example_files/single_row.csv
new file mode 100644
index 0000000..8c9c3c6
--- /dev/null
+++ b/tests/example_files/single_row.csv
@@ -0,0 +1 @@
+C1,C2,C3
diff --git a/tests/methods/ParseTest.php b/tests/methods/ParseTest.php
index 7eb2ddf..22c8655 100644
--- a/tests/methods/ParseTest.php
+++ b/tests/methods/ParseTest.php
@@ -121,6 +121,15 @@ class ParseTest extends TestCase {
         self::assertEquals($expected, $this->csv->data);
     }
 
+    public function testSingleRow() {
+        $this->csv->auto(__DIR__ . '/../example_files/single_row.csv');
+        self::assertEquals([], $this->csv->data, 'Single row is detected as header');
+        $this->csv->heading = false;
+        $this->csv->auto(__DIR__ . '/../example_files/single_row.csv');
+        $expected = [['C1', 'C2', 'C3']];
+        self::assertEquals($expected, $this->csv->data);
+    }
+
     public function testMatomoData() {
         // Matomo (Piwik) export cannot be read with
         $this->csv->use_mb_convert_encoding = true;