diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
index 23b3d630..36e9eacf 100644
--- a/phpstan-baseline.neon
+++ b/phpstan-baseline.neon
@@ -5510,66 +5510,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Spreadsheet.php
 
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Alignment.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Border.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getStyleArray\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Border.php
-
-		-
-			message: "#^Parameter \\#1 \\$parent of method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Supervisor\\:\\:bindParent\\(\\) expects PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style, \\$this\\(PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Border\\) given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Border.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Borders.php
-
-		-
-			message: "#^Parameter \\#1 \\$parent of method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Supervisor\\:\\:bindParent\\(\\) expects PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style, \\$this\\(PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Borders\\) given\\.$#"
-			count: 10
-			path: src/PhpSpreadsheet/Style/Borders.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getStyleArray\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Border\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Fill\\:\\:getColor\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Border\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Fill\\:\\:getEndColor\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Border\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Fill\\:\\:getStartColor\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
-		-
-			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Color\\:\\:getColourComponent\\(\\) should return int\\|string but returns float\\|int\\|string\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Color.php
-
 		-
 			message: "#^Property PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Conditional\\:\\:\\$condition \\(array\\<string\\>\\) does not accept array\\<bool\\|float\\|int\\|string\\>\\.$#"
 			count: 1
@@ -5740,36 +5680,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Style/ConditionalFormatting/ConditionalFormattingRuleExtension.php
 
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Fill.php
-
-		-
-			message: "#^Parameter \\#1 \\$parent of method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Supervisor\\:\\:bindParent\\(\\) expects PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style, \\$this\\(PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Fill\\) given\\.$#"
-			count: 2
-			path: src/PhpSpreadsheet/Style/Fill.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Font.php
-
-		-
-			message: "#^Parameter \\#1 \\$parent of method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Supervisor\\:\\:bindParent\\(\\) expects PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style, \\$this\\(PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Font\\) given\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Font.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/NumberFormat.php
-
-		-
-			message: "#^Property PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\NumberFormat\\:\\:\\$builtInFormatCode \\(int\\|false\\) does not accept bool\\|int\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/NumberFormat.php
-
 		-
 			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\NumberFormat\\\\DateFormatter\\:\\:escapeQuotesCallback\\(\\) has parameter \\$matches with no type specified\\.$#"
 			count: 1
@@ -5900,21 +5810,6 @@ parameters:
 			count: 1
 			path: src/PhpSpreadsheet/Style/NumberFormat/PercentageFormatter.php
 
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getSharedComponent\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Protection.php
-
-		-
-			message: "#^Call to an undefined method PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getCellXfByIndex\\(\\)\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Style.php
-
-		-
-			message: "#^Method PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\:\\:getParent\\(\\) should return PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet but returns PhpOffice\\\\PhpSpreadsheet\\\\Spreadsheet\\|PhpOffice\\\\PhpSpreadsheet\\\\Style\\\\Style\\.$#"
-			count: 1
-			path: src/PhpSpreadsheet/Style/Style.php
-
 		-
 			message: "#^Argument of an invalid type mixed supplied for foreach, only iterables are supported\\.$#"
 			count: 1
diff --git a/samples/Basic/47_xlsfill.php b/samples/Basic/47_xlsfill.php
new file mode 100644
index 00000000..217d7dca
--- /dev/null
+++ b/samples/Basic/47_xlsfill.php
@@ -0,0 +1,13 @@
+<?php
+
+require __DIR__ . '/../Header.php';
+
+use PhpOffice\PhpSpreadsheet\Reader\Xls;
+
+$helper->log('Read spreadsheet');
+$reader = new Xls();
+$spreadsheet = $reader->load(__DIR__ . '/../templates/47_xlsfill.xls');
+
+// Save
+$helper->write($spreadsheet, __FILE__, ['Xls']);
+$spreadsheet->disconnectWorksheets();
diff --git a/samples/Basic/47_xlsxfill.php b/samples/Basic/47_xlsxfill.php
new file mode 100644
index 00000000..c19d789d
--- /dev/null
+++ b/samples/Basic/47_xlsxfill.php
@@ -0,0 +1,13 @@
+<?php
+
+require __DIR__ . '/../Header.php';
+
+use PhpOffice\PhpSpreadsheet\Reader\Xlsx;
+
+$helper->log('Read spreadsheet');
+$reader = new Xlsx();
+$spreadsheet = $reader->load(__DIR__ . '/../templates/47_xlsxfill.xlsx');
+
+// Save
+$helper->write($spreadsheet, __FILE__, ['Xlsx']);
+$spreadsheet->disconnectWorksheets();
diff --git a/samples/templates/47_xlsfill.xls b/samples/templates/47_xlsfill.xls
new file mode 100644
index 00000000..71887217
Binary files /dev/null and b/samples/templates/47_xlsfill.xls differ
diff --git a/samples/templates/47_xlsxfill.xlsx b/samples/templates/47_xlsxfill.xlsx
new file mode 100644
index 00000000..ace23614
Binary files /dev/null and b/samples/templates/47_xlsxfill.xlsx differ
diff --git a/src/PhpSpreadsheet/Style/Alignment.php b/src/PhpSpreadsheet/Style/Alignment.php
index 1b3ed6ac..83ac5b0d 100644
--- a/src/PhpSpreadsheet/Style/Alignment.php
+++ b/src/PhpSpreadsheet/Style/Alignment.php
@@ -111,7 +111,10 @@ class Alignment extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getAlignment();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getAlignment();
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/Border.php b/src/PhpSpreadsheet/Style/Border.php
index 9fabf366..a5ec980a 100644
--- a/src/PhpSpreadsheet/Style/Border.php
+++ b/src/PhpSpreadsheet/Style/Border.php
@@ -70,8 +70,11 @@ class Border extends Supervisor
      */
     public function getSharedComponent()
     {
+        /** @var Style */
+        $parent = $this->parent;
+
         /** @var Borders $sharedComponent */
-        $sharedComponent = $this->parent->getSharedComponent();
+        $sharedComponent = $parent->getSharedComponent();
         switch ($this->parentPropertyName) {
             case 'bottom':
                 return $sharedComponent->getBottom();
@@ -97,7 +100,10 @@ class Border extends Supervisor
      */
     public function getStyleArray($array)
     {
-        return $this->parent->getStyleArray([$this->parentPropertyName => $array]);
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getStyleArray([$this->parentPropertyName => $array]);
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/Borders.php b/src/PhpSpreadsheet/Style/Borders.php
index 5d92f935..56a52709 100644
--- a/src/PhpSpreadsheet/Style/Borders.php
+++ b/src/PhpSpreadsheet/Style/Borders.php
@@ -140,7 +140,10 @@ class Borders extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getBorders();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getBorders();
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/Color.php b/src/PhpSpreadsheet/Style/Color.php
index d9b9830c..c2d4f749 100644
--- a/src/PhpSpreadsheet/Style/Color.php
+++ b/src/PhpSpreadsheet/Style/Color.php
@@ -45,6 +45,9 @@ class Color extends Supervisor
      */
     protected $argb;
 
+    /** @var bool */
+    private $hasChanged = false;
+
     /**
      * Create a new Color.
      *
@@ -75,12 +78,15 @@ class Color extends Supervisor
      */
     public function getSharedComponent()
     {
+        /** @var Style */
+        $parent = $this->parent;
         /** @var Border|Fill $sharedComponent */
-        $sharedComponent = $this->parent->getSharedComponent();
-        if ($this->parentPropertyName === 'endColor') {
-            return $sharedComponent->getEndColor();
-        }
-        if ($this->parentPropertyName === 'startColor') {
+        $sharedComponent = $parent->getSharedComponent();
+        if ($sharedComponent instanceof Fill) {
+            if ($this->parentPropertyName === 'endColor') {
+                return $sharedComponent->getEndColor();
+            }
+
             return $sharedComponent->getStartColor();
         }
 
@@ -96,7 +102,10 @@ class Color extends Supervisor
      */
     public function getStyleArray($array)
     {
-        return $this->parent->getStyleArray([$this->parentPropertyName => $array]);
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getStyleArray([$this->parentPropertyName => $array]);
     }
 
     /**
@@ -153,6 +162,7 @@ class Color extends Supervisor
      */
     public function setARGB(?string $colorValue = self::COLOR_BLACK)
     {
+        $this->hasChanged = true;
         if ($colorValue === '' || $colorValue === null) {
             $colorValue = self::COLOR_BLACK;
         } elseif (!$this->validateColor($colorValue, self::VALIDATE_ARGB_SIZE)) {
@@ -190,6 +200,7 @@ class Color extends Supervisor
      */
     public function setRGB(?string $colorValue = self::COLOR_BLACK)
     {
+        $this->hasChanged = true;
         if ($colorValue === '' || $colorValue === null) {
             $colorValue = '000000';
         } elseif (!$this->validateColor($colorValue, self::VALIDATE_RGB_SIZE)) {
@@ -220,7 +231,7 @@ class Color extends Supervisor
     {
         $colour = substr($rgbValue, $offset, 2);
 
-        return ($hex) ? $colour : hexdec($colour);
+        return ($hex) ? $colour : (int) hexdec($colour);
     }
 
     /**
@@ -410,4 +421,13 @@ class Color extends Supervisor
 
         return $exportedArray;
     }
+
+    public function getHasChanged(): bool
+    {
+        if ($this->isSupervisor) {
+            return $this->getSharedComponent()->hasChanged;
+        }
+
+        return $this->hasChanged;
+    }
 }
diff --git a/src/PhpSpreadsheet/Style/Fill.php b/src/PhpSpreadsheet/Style/Fill.php
index 1a7331eb..bd87a792 100644
--- a/src/PhpSpreadsheet/Style/Fill.php
+++ b/src/PhpSpreadsheet/Style/Fill.php
@@ -49,7 +49,7 @@ class Fill extends Supervisor
      *
      * @var float
      */
-    protected $rotation = 0;
+    protected $rotation = 0.0;
 
     /**
      * Start color.
@@ -65,6 +65,9 @@ class Fill extends Supervisor
      */
     protected $endColor;
 
+    /** @var bool */
+    private $colorChanged = false;
+
     /**
      * Create a new Fill.
      *
@@ -102,7 +105,10 @@ class Fill extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getFill();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getFill();
     }
 
     /**
@@ -124,7 +130,7 @@ class Fill extends Supervisor
      * $spreadsheet->getActiveSheet()->getStyle('B2')->getFill()->applyFromArray(
      *     [
      *         'fillType' => Fill::FILL_GRADIENT_LINEAR,
-     *         'rotation' => 0,
+     *         'rotation' => 0.0,
      *         'startColor' => [
      *             'rgb' => '000000'
      *         ],
@@ -248,6 +254,7 @@ class Fill extends Supervisor
      */
     public function setStartColor(Color $color)
     {
+        $this->colorChanged = true;
         // make sure parameter is a real color and not a supervisor
         $color = $color->getIsSupervisor() ? $color->getSharedComponent() : $color;
 
@@ -278,6 +285,7 @@ class Fill extends Supervisor
      */
     public function setEndColor(Color $color)
     {
+        $this->colorChanged = true;
         // make sure parameter is a real color and not a supervisor
         $color = $color->getIsSupervisor() ? $color->getSharedComponent() : $color;
 
@@ -291,6 +299,17 @@ class Fill extends Supervisor
         return $this;
     }
 
+    public function getColorsChanged(): bool
+    {
+        if ($this->isSupervisor) {
+            $changed = $this->getSharedComponent()->colorChanged;
+        } else {
+            $changed = $this->colorChanged;
+        }
+
+        return $changed || $this->startColor->getHasChanged() || $this->endColor->getHasChanged();
+    }
+
     /**
      * Get hash code.
      *
@@ -308,6 +327,7 @@ class Fill extends Supervisor
             $this->getRotation() .
             ($this->getFillType() !== self::FILL_NONE ? $this->getStartColor()->getHashCode() : '') .
             ($this->getFillType() !== self::FILL_NONE ? $this->getEndColor()->getHashCode() : '') .
+            ((string) $this->getColorsChanged()) .
             __CLASS__
         );
     }
@@ -315,10 +335,12 @@ class Fill extends Supervisor
     protected function exportArray1(): array
     {
         $exportedArray = [];
-        $this->exportArray2($exportedArray, 'endColor', $this->getEndColor());
         $this->exportArray2($exportedArray, 'fillType', $this->getFillType());
         $this->exportArray2($exportedArray, 'rotation', $this->getRotation());
-        $this->exportArray2($exportedArray, 'startColor', $this->getStartColor());
+        if ($this->getColorsChanged()) {
+            $this->exportArray2($exportedArray, 'endColor', $this->getEndColor());
+            $this->exportArray2($exportedArray, 'startColor', $this->getStartColor());
+        }
 
         return $exportedArray;
     }
diff --git a/src/PhpSpreadsheet/Style/Font.php b/src/PhpSpreadsheet/Style/Font.php
index 63a75cc5..13fe2b67 100644
--- a/src/PhpSpreadsheet/Style/Font.php
+++ b/src/PhpSpreadsheet/Style/Font.php
@@ -122,7 +122,10 @@ class Font extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getFont();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getFont();
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/NumberFormat.php b/src/PhpSpreadsheet/Style/NumberFormat.php
index a4569283..536b1d54 100644
--- a/src/PhpSpreadsheet/Style/NumberFormat.php
+++ b/src/PhpSpreadsheet/Style/NumberFormat.php
@@ -104,7 +104,10 @@ class NumberFormat extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getNumberFormat();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getNumberFormat();
     }
 
     /**
@@ -157,7 +160,7 @@ class NumberFormat extends Supervisor
         if ($this->isSupervisor) {
             return $this->getSharedComponent()->getFormatCode();
         }
-        if ($this->builtInFormatCode !== false) {
+        if (is_int($this->builtInFormatCode)) {
             return self::builtInFormatCode($this->builtInFormatCode);
         }
 
@@ -352,7 +355,7 @@ class NumberFormat extends Supervisor
      *
      * @param string $formatCodeIndex
      *
-     * @return bool|int
+     * @return false|int
      */
     public static function builtInFormatCodeIndex($formatCodeIndex)
     {
diff --git a/src/PhpSpreadsheet/Style/Protection.php b/src/PhpSpreadsheet/Style/Protection.php
index fc15e3b8..1c174e72 100644
--- a/src/PhpSpreadsheet/Style/Protection.php
+++ b/src/PhpSpreadsheet/Style/Protection.php
@@ -53,7 +53,10 @@ class Protection extends Supervisor
      */
     public function getSharedComponent()
     {
-        return $this->parent->getSharedComponent()->getProtection();
+        /** @var Style */
+        $parent = $this->parent;
+
+        return $parent->getSharedComponent()->getProtection();
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/Style.php b/src/PhpSpreadsheet/Style/Style.php
index 5823929d..fdb15451 100644
--- a/src/PhpSpreadsheet/Style/Style.php
+++ b/src/PhpSpreadsheet/Style/Style.php
@@ -132,17 +132,15 @@ class Style extends Supervisor
             $xfIndex = 0;
         }
 
-        return $this->parent->getCellXfByIndex($xfIndex);
+        return $activeSheet->getParent()->getCellXfByIndex($xfIndex);
     }
 
     /**
      * Get parent. Only used for style supervisor.
-     *
-     * @return Spreadsheet
      */
-    public function getParent()
+    public function getParent(): Spreadsheet
     {
-        return $this->parent;
+        return $this->getActiveSheet()->getParent();
     }
 
     /**
diff --git a/src/PhpSpreadsheet/Style/Supervisor.php b/src/PhpSpreadsheet/Style/Supervisor.php
index 7f655bef..8a5c350d 100644
--- a/src/PhpSpreadsheet/Style/Supervisor.php
+++ b/src/PhpSpreadsheet/Style/Supervisor.php
@@ -18,7 +18,7 @@ abstract class Supervisor implements IComparable
     /**
      * Parent. Only used for supervisor.
      *
-     * @var Spreadsheet|Style
+     * @var Spreadsheet|Supervisor
      */
     protected $parent;
 
@@ -45,7 +45,7 @@ abstract class Supervisor implements IComparable
     /**
      * Bind parent. Only used for supervisor.
      *
-     * @param Spreadsheet|Style $parent
+     * @param Spreadsheet|Supervisor $parent
      * @param null|string $parentPropertyName
      *
      * @return $this
@@ -155,4 +155,21 @@ abstract class Supervisor implements IComparable
             $exportedArray[$index] = $objOrValue;
         }
     }
+
+    /**
+     * Get the shared style component for the currently active cell in currently active sheet.
+     * Only used for style supervisor.
+     *
+     * @return mixed
+     */
+    abstract public function getSharedComponent();
+
+    /**
+     * Build style array from subcomponents.
+     *
+     * @param array $array
+     *
+     * @return array
+     */
+    abstract public function getStyleArray($array);
 }
diff --git a/src/PhpSpreadsheet/Writer/Xlsx/Style.php b/src/PhpSpreadsheet/Writer/Xlsx/Style.php
index bf306a80..cb2e3850 100644
--- a/src/PhpSpreadsheet/Writer/Xlsx/Style.php
+++ b/src/PhpSpreadsheet/Writer/Xlsx/Style.php
@@ -201,6 +201,15 @@ class Style extends WriterPart
         $objWriter->endElement();
     }
 
+    private static function writePatternColors(Fill $fill): bool
+    {
+        if ($fill->getFillType() === Fill::FILL_NONE) {
+            return false;
+        }
+
+        return $fill->getFillType() === Fill::FILL_SOLID || $fill->getColorsChanged();
+    }
+
     /**
      * Write Pattern Fill.
      */
@@ -213,15 +222,13 @@ class Style extends WriterPart
         $objWriter->startElement('patternFill');
         $objWriter->writeAttribute('patternType', $fill->getFillType());
 
-        if ($fill->getFillType() !== Fill::FILL_NONE) {
+        if (self::writePatternColors($fill)) {
             // fgColor
             if ($fill->getStartColor()->getARGB()) {
                 $objWriter->startElement('fgColor');
                 $objWriter->writeAttribute('rgb', $fill->getStartColor()->getARGB());
                 $objWriter->endElement();
             }
-        }
-        if ($fill->getFillType() !== Fill::FILL_NONE) {
             // bgColor
             if ($fill->getEndColor()->getARGB()) {
                 $objWriter->startElement('bgColor');
diff --git a/tests/PhpSpreadsheetTests/Style/ExportArrayTest.php b/tests/PhpSpreadsheetTests/Style/ExportArrayTest.php
index e11e5f29..a062b4cf 100644
--- a/tests/PhpSpreadsheetTests/Style/ExportArrayTest.php
+++ b/tests/PhpSpreadsheetTests/Style/ExportArrayTest.php
@@ -51,6 +51,7 @@ class ExportArrayTest extends TestCase
         self::AssertEquals($cell1style->getFont()->getHashCode(), $cell2style->getFont()->getHashCode());
         self::AssertEquals($cell1style->getFill()->getHashCode(), $cell2style->getFill()->getHashCode());
         self::AssertEquals($cell1style->getProtection()->getHashCode(), $cell2style->getProtection()->getHashCode());
+        $spreadsheet->disconnectWorksheets();
     }
 
     public function testStyleFromArrayCopy(): void
@@ -89,6 +90,7 @@ class ExportArrayTest extends TestCase
 
         self::AssertEquals($cell1style->getFill()->getStartColor()->getHashCode(), $cell2style->getFill()->getStartColor()->getHashCode());
         self::AssertEquals($cell1style->getFill()->getEndColor()->getHashCode(), $cell2style->getFill()->getEndColor()->getHashCode());
+        $spreadsheet->disconnectWorksheets();
     }
 
     public function testNumberFormat(): void
@@ -112,6 +114,7 @@ class ExportArrayTest extends TestCase
         self::assertEquals('$ 12,345.679', $cell2->getFormattedValue());
 
         self::AssertEquals($cell1style->getNumberFormat()->getHashCode(), $cell2style->getNumberFormat()->getHashCode());
+        $spreadsheet->disconnectWorksheets();
     }
 
     public function testNumberFormatFromArray(): void
@@ -139,6 +142,7 @@ class ExportArrayTest extends TestCase
         self::AssertEquals($cell1style->getBorders()->getHashCode(), $cell2style->getBorders()->getHashCode());
         self::AssertEquals($cell1style->getBorders()->getTop()->getHashCode(), $cell2style->getBorders()->getTop()->getHashCode());
         self::AssertEquals($cell1style->getBorders()->getTop()->getBorderStyle(), $cell2style->getBorders()->getTop()->getBorderStyle());
+        $spreadsheet->disconnectWorksheets();
     }
 
     public function testStackedRotation(): void
@@ -157,5 +161,128 @@ class ExportArrayTest extends TestCase
         $cell2style->applyFromArray($styleArray);
 
         self::AssertEquals($cell1style->getAlignment()->getTextRotation(), $cell2style->getAlignment()->getTextRotation());
+        $spreadsheet->disconnectWorksheets();
+    }
+
+    public function testFillColors(): void
+    {
+        $spreadsheet = new Spreadsheet();
+        $sheet = $spreadsheet->getActiveSheet();
+
+        $cell1 = $sheet->getCell('A2');
+        $cell1style = $cell1->getStyle();
+        $cell1style->getFill()->setFillType(Fill::FILL_PATTERN_GRAY125);
+        $cell1style->getFill()->getStartColor()->setArgb('FF112233');
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+                'endColor' => ['argb' => 'FF000000'],
+                'startColor' => ['argb' => 'FF112233'],
+            ],
+            $styleArray['fill'],
+            'changed start color with setArgb'
+        );
+
+        $cell1 = $sheet->getCell('A1');
+        $cell1style = $cell1->getStyle();
+        $cell1style->getFill()->setFillType(Fill::FILL_PATTERN_GRAY125);
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+            ],
+            $styleArray['fill'],
+            'default colors'
+        );
+
+        $cell1 = $sheet->getCell('A3');
+        $cell1style = $cell1->getStyle();
+        $cell1style->getFill()->setFillType(Fill::FILL_PATTERN_GRAY125);
+        $cell1style->getFill()->getEndColor()->setArgb('FF112233');
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+                'endColor' => ['argb' => 'FF112233'],
+                'startColor' => ['argb' => 'FFFFFFFF'],
+            ],
+            $styleArray['fill'],
+            'changed end color with setArgb'
+        );
+
+        $cell1 = $sheet->getCell('A4');
+        $cell1style = $cell1->getStyle();
+        $cell1style->getFill()->setFillType(Fill::FILL_PATTERN_GRAY125);
+        $cell1style->getFill()->setEndColor(new Color('FF0000FF'));
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+                'endColor' => ['argb' => 'FF0000FF'],
+                'startColor' => ['argb' => 'FFFFFFFF'],
+            ],
+            $styleArray['fill'],
+            'changed end color with setEndColor'
+        );
+
+        $cell1 = $sheet->getCell('A5');
+        $cell1style = $cell1->getStyle();
+        $cell1style->getFill()->setFillType(Fill::FILL_PATTERN_GRAY125);
+        $cell1style->getFill()->setStartColor(new Color('FF0000FF'));
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+                'startColor' => ['argb' => 'FF0000FF'],
+                'endColor' => ['argb' => 'FF000000'],
+            ],
+            $styleArray['fill'],
+            'changed start color with setStartColor'
+        );
+
+        $cell1 = $sheet->getCell('A6');
+        $cell1->getStyle()->getFill()->applyFromArray(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 45.0,
+                'startColor' => ['argb' => 'FF00FFFF'],
+            ]
+        );
+        $cell1style = $cell1->getStyle();
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 45.0,
+                'startColor' => ['argb' => 'FF00FFFF'],
+                'endColor' => ['argb' => 'FF000000'],
+            ],
+            $styleArray['fill'],
+            'applyFromArray with startColor'
+        );
+
+        $cell1 = $sheet->getCell('A7');
+        $cell1->getStyle()->getFill()->applyFromArray(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+            ]
+        );
+        $cell1style = $cell1->getStyle();
+        $styleArray = $cell1style->exportArray();
+        self::assertEquals(
+            [
+                'fillType' => Fill::FILL_PATTERN_GRAY125,
+                'rotation' => 0.0,
+            ],
+            $styleArray['fill'],
+            'applyFromArray without start/endColor'
+        );
+        $spreadsheet->disconnectWorksheets();
     }
 }