diff --git a/src/PhpSpreadsheet/Calculation/TextData/Extract.php b/src/PhpSpreadsheet/Calculation/TextData/Extract.php
index 519607c080..24ddff2ec5 100644
--- a/src/PhpSpreadsheet/Calculation/TextData/Extract.php
+++ b/src/PhpSpreadsheet/Calculation/TextData/Extract.php
@@ -261,7 +261,7 @@ private static function buildDelimiter($delimiter): string
             $delimiter = Functions::flattenArray($delimiter);
             $quotedDelimiters = array_map(
                 function ($delimiter) {
-                    return preg_quote($delimiter ?? '');
+                    return preg_quote($delimiter ?? '', '/');
                 },
                 $delimiter
             );
@@ -270,7 +270,7 @@ function ($delimiter) {
             return '(' . $delimiters . ')';
         }
 
-        return '(' . preg_quote($delimiter ?? '') . ')';
+        return '(' . preg_quote($delimiter ?? '', '/') . ')';
     }
 
     private static function matchFlags(int $matchMode): string
diff --git a/src/PhpSpreadsheet/Calculation/TextData/Format.php b/src/PhpSpreadsheet/Calculation/TextData/Format.php
index 06433e4b13..57d3316637 100644
--- a/src/PhpSpreadsheet/Calculation/TextData/Format.php
+++ b/src/PhpSpreadsheet/Calculation/TextData/Format.php
@@ -294,7 +294,7 @@ public static function NUMBERVALUE($value = '', $decimalSeparator = null, $group
         }
 
         if (!is_numeric($value)) {
-            $decimalPositions = preg_match_all('/' . preg_quote($decimalSeparator) . '/', $value, $matches, PREG_OFFSET_CAPTURE);
+            $decimalPositions = preg_match_all('/' . preg_quote($decimalSeparator, '/') . '/', $value, $matches, PREG_OFFSET_CAPTURE);
             if ($decimalPositions > 1) {
                 return ExcelError::VALUE();
             }
diff --git a/src/PhpSpreadsheet/Calculation/TextData/Text.php b/src/PhpSpreadsheet/Calculation/TextData/Text.php
index 8e6a575a29..b8a730767c 100644
--- a/src/PhpSpreadsheet/Calculation/TextData/Text.php
+++ b/src/PhpSpreadsheet/Calculation/TextData/Text.php
@@ -193,7 +193,7 @@ private static function buildDelimiter($delimiter): string
         if (is_array($delimiter) && count($valueSet) > 1) {
             $quotedDelimiters = array_map(
                 function ($delimiter) {
-                    return preg_quote($delimiter ?? '');
+                    return preg_quote($delimiter ?? '', '/');
                 },
                 $valueSet
             );
@@ -202,7 +202,7 @@ function ($delimiter) {
             return '(' . $delimiters . ')';
         }
 
-        return '(' . preg_quote(/** @scrutinizer ignore-type */ Functions::flattenSingleValue($delimiter)) . ')';
+        return '(' . preg_quote(/** @scrutinizer ignore-type */ Functions::flattenSingleValue($delimiter), '/') . ')';
     }
 
     private static function matchFlags(bool $matchMode): string
diff --git a/tests/data/Calculation/TextData/NUMBERVALUE.php b/tests/data/Calculation/TextData/NUMBERVALUE.php
index e72194067f..6131317426 100644
--- a/tests/data/Calculation/TextData/NUMBERVALUE.php
+++ b/tests/data/Calculation/TextData/NUMBERVALUE.php
@@ -51,6 +51,8 @@
     ],
     'no arguments' => ['exception'],
     'boolean argument' => ['#VALUE!', true],
+    'slash as group separator' => [1234567.1, '1/234/567.1', '.', '/'],
+    'slash as decimal separator' => [1234567.1, '1,234,567/1', '/', ','],
     'issue 3574 null string treated as 0' => [0, '', ',', ' '],
     'issue 3574 one or more spaces treated as 0' => [0, '   ', ',', ' '],
     'issue 3574 non-blank numeric string okay' => [2, ' 2 ', ',', ' '],
diff --git a/tests/data/Calculation/TextData/TEXTAFTER.php b/tests/data/Calculation/TextData/TEXTAFTER.php
index ebcfecb946..c0e3e3d51f 100644
--- a/tests/data/Calculation/TextData/TEXTAFTER.php
+++ b/tests/data/Calculation/TextData/TEXTAFTER.php
@@ -248,4 +248,11 @@
             1,
         ],
     ],
+    'slash delimiter' => [
+        'about/that',
+        [
+            'How/about/that',
+            '/',
+        ],
+    ],
 ];
diff --git a/tests/data/Calculation/TextData/TEXTBEFORE.php b/tests/data/Calculation/TextData/TEXTBEFORE.php
index 1929354ce5..a79d37b0fd 100644
--- a/tests/data/Calculation/TextData/TEXTBEFORE.php
+++ b/tests/data/Calculation/TextData/TEXTBEFORE.php
@@ -240,4 +240,11 @@
             1,
         ],
     ],
+    'slash delimiter' => [
+        'How',
+        [
+            'How/about/that',
+            '/',
+        ],
+    ],
 ];
diff --git a/tests/data/Calculation/TextData/TEXTSPLIT.php b/tests/data/Calculation/TextData/TEXTSPLIT.php
index 64016ca7a7..a10b26f6e8 100644
--- a/tests/data/Calculation/TextData/TEXTSPLIT.php
+++ b/tests/data/Calculation/TextData/TEXTSPLIT.php
@@ -104,4 +104,20 @@
             '',
         ],
     ],
+    'slash as column delimiter' => [
+        [['Hello', 'World']],
+        [
+            'Hello/World',
+            '/',
+            '',
+        ],
+    ],
+    'slash as row delimiter' => [
+        [['ho', 'w'], ['about', '#N/A'], ['t', 'hat']],
+        [
+            'ho.w/about/t.hat',
+            '.',
+            '/',
+        ],
+    ],
 ];