diff --git a/composer.json b/composer.json
index c7513cc79..45e1390df 100644
--- a/composer.json
+++ b/composer.json
@@ -25,7 +25,7 @@
         "bramus/monolog-colored-line-formatter": "~2.0",
         "composer/installers": "~1.0",
         "embed/embed": "^3.0",
-        "league/csv": "^8",
+        "league/csv": "^8 || ^9",
         "league/flysystem": "~1.0.12",
         "m1/env": "^2.1",
         "monolog/monolog": "~1.11",
@@ -54,7 +54,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^5.7",
-        "sminnee/phpunit-mock-objects": "^3.4.5",
+        "sminnee/phpunit-mock-objects": "^3.4.9",
         "silverstripe/versioned": "^1",
         "squizlabs/php_codesniffer": "^3.5"
     },
diff --git a/src/Dev/CsvBulkLoader.php b/src/Dev/CsvBulkLoader.php
index 5a3a0a56c..f90f76eca 100644
--- a/src/Dev/CsvBulkLoader.php
+++ b/src/Dev/CsvBulkLoader.php
@@ -2,6 +2,7 @@
 
 namespace SilverStripe\Dev;
 
+use League\Csv\MapIterator;
 use League\Csv\Reader;
 use SilverStripe\Control\Director;
 use SilverStripe\ORM\DataObject;
@@ -76,9 +77,16 @@ class CsvBulkLoader extends BulkLoader
             $filepath = Director::getAbsFile($filepath);
             $csvReader = Reader::createFromPath($filepath, 'r');
             $csvReader->setDelimiter($this->delimiter);
-            $csvReader->stripBom(true);
 
-            $tabExtractor = function ($row, $rowOffset, $iterator) {
+            // league/csv 9
+            if (method_exists($csvReader, 'skipInputBOM')) {
+                $csvReader->skipInputBOM();
+            // league/csv 8
+            } else {
+                $csvReader->stripBom(true);
+            }
+
+            $tabExtractor = function ($row, $rowOffset) {
                 foreach ($row as &$item) {
                     // [SS-2017-007] Ensure all cells with leading tab and then [@=+] have the tab removed on import
                     if (preg_match("/^\t[\-@=\+]+.*/", $item)) {
@@ -90,8 +98,9 @@ class CsvBulkLoader extends BulkLoader
 
             if ($this->columnMap) {
                 $headerMap = $this->getNormalisedColumnMap();
-                $remapper = function ($row, $rowOffset, $iterator) use ($headerMap, $tabExtractor) {
-                    $row = $tabExtractor($row, $rowOffset, $iterator);
+
+                $remapper = function ($row, $rowOffset) use ($headerMap, $tabExtractor) {
+                    $row = $tabExtractor($row, $rowOffset);
                     foreach ($headerMap as $column => $renamedColumn) {
                         if ($column == $renamedColumn) {
                             continue;
@@ -110,9 +119,18 @@ class CsvBulkLoader extends BulkLoader
             }
 
             if ($this->hasHeaderRow) {
-                $rows = $csvReader->fetchAssoc(0, $remapper);
+                if (method_exists($csvReader, 'fetchAssoc')) {
+                    $rows = $csvReader->fetchAssoc(0, $remapper);
+                } else {
+                    $csvReader->setHeaderOffset(0);
+                    $rows = new MapIterator($csvReader->getRecords(), $remapper);
+                }
             } elseif ($this->columnMap) {
-                $rows = $csvReader->fetchAssoc($headerMap, $remapper);
+                if (method_exists($csvReader, 'fetchAssoc')) {
+                    $rows = $csvReader->fetchAssoc($headerMap, $remapper);
+                } else {
+                    $rows = new MapIterator($csvReader->getRecords($headerMap), $remapper);
+                }
             }
 
             foreach ($rows as $row) {
diff --git a/src/Forms/GridField/GridFieldExportButton.php b/src/Forms/GridField/GridFieldExportButton.php
index 02b6a6c87..8d5b3b427 100644
--- a/src/Forms/GridField/GridFieldExportButton.php
+++ b/src/Forms/GridField/GridFieldExportButton.php
@@ -257,6 +257,10 @@ class GridFieldExportButton implements GridField_HTMLProvider, GridField_ActionP
             }
         }
 
+        if (method_exists($csvWriter, 'getContent')) {
+            return $csvWriter->getContent();
+        }
+
         return (string)$csvWriter;
     }
 
diff --git a/tests/php/Forms/GridField/GridFieldExportButtonTest.php b/tests/php/Forms/GridField/GridFieldExportButtonTest.php
index 5738beb98..222d5f657 100644
--- a/tests/php/Forms/GridField/GridFieldExportButtonTest.php
+++ b/tests/php/Forms/GridField/GridFieldExportButtonTest.php
@@ -55,7 +55,7 @@ class GridFieldExportButtonTest extends SapphireTest
         $config = GridFieldConfig::create()->addComponent(new GridFieldExportButton());
         $gridField = new GridField('testfield', 'testfield', $list, $config);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -69,7 +69,7 @@ class GridFieldExportButtonTest extends SapphireTest
         $button = new GridFieldExportButton();
         $button->setExportColumns(['Name' => 'My Name']);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -89,7 +89,7 @@ class GridFieldExportButtonTest extends SapphireTest
         $button = new GridFieldExportButton();
         $button->setExportColumns(['Name' => 'My Name']);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -108,7 +108,7 @@ class GridFieldExportButtonTest extends SapphireTest
             }
         ]);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -125,7 +125,7 @@ class GridFieldExportButtonTest extends SapphireTest
             'City' => 'strtolower',
         ]);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -143,7 +143,7 @@ class GridFieldExportButtonTest extends SapphireTest
         ]);
         $button->setCsvHasHeader(false);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -167,7 +167,7 @@ class GridFieldExportButtonTest extends SapphireTest
 
         $exportData = $button->generateExportFileData($this->gridField);
 
-        $csvReader = Reader::createFromString($exportData);
+        $csvReader = $this->createReader($exportData);
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -183,7 +183,7 @@ class GridFieldExportButtonTest extends SapphireTest
             'RugbyTeamNumber' => 'Rugby Team Number'
         ]);
 
-        $csvReader = Reader::createFromString($button->generateExportFileData($this->gridField));
+        $csvReader = $this->createReader($button->generateExportFileData($this->gridField));
         $bom = $csvReader->getInputBOM();
 
         $this->assertEquals(
@@ -191,4 +191,16 @@ class GridFieldExportButtonTest extends SapphireTest
             (string) $csvReader
         );
     }
+
+    protected function createReader($string)
+    {
+        $reader = Reader::createFromString($string);
+
+        // Explicitly set the output BOM in league/csv 9
+        if (method_exists($reader, 'getContent')) {
+            $reader->setOutputBOM(Reader::BOM_UTF8);
+        }
+
+        return $reader;
+    }
 }