diff --git a/src/Fixer/FunctionNotation/AlignMultilineParametersFixer.php b/src/Fixer/FunctionNotation/AlignMultilineParametersFixer.php
index b357968..7fe2b23 100644
--- a/src/Fixer/FunctionNotation/AlignMultilineParametersFixer.php
+++ b/src/Fixer/FunctionNotation/AlignMultilineParametersFixer.php
@@ -14,14 +14,35 @@ use PhpCsFixer\FixerDefinition\FixerDefinition;
 use PhpCsFixer\FixerDefinition\FixerDefinitionInterface;
 use PhpCsFixer\Tokenizer\Analyzer\FunctionsAnalyzer;
 use PhpCsFixer\Tokenizer\Analyzer\WhitespacesAnalyzer;
+use PhpCsFixer\Tokenizer\CT;
 use PhpCsFixer\Tokenizer\Tokens;
 use PhpCsFixer\Tokenizer\TokensAnalyzer;
 use SplFileInfo;
 
 final class AlignMultilineParametersFixer extends AbstractFixer implements ConfigurableFixerInterface, WhitespacesAwareFixerInterface {
 
-    private const C_VARIABLES = 'variables';
-    private const C_DEFAULTS = 'defaults';
+    /**
+     * @internal
+     */
+    public const C_VARIABLES = 'variables';
+    /**
+     * @internal
+     */
+    public const C_DEFAULTS = 'defaults';
+
+    private array $parameterModifiers;
+
+    public function __construct() {
+        parent::__construct();
+        $this->parameterModifiers = [
+            CT::T_CONSTRUCTOR_PROPERTY_PROMOTION_PUBLIC,
+            CT::T_CONSTRUCTOR_PROPERTY_PROMOTION_PROTECTED,
+            CT::T_CONSTRUCTOR_PROPERTY_PROMOTION_PRIVATE,
+        ];
+        if (defined('T_READONLY')) {
+            $this->parameterModifiers[] = T_READONLY;
+        }
+    }
 
     public function getDefinition(): FixerDefinitionInterface {
         return new FixerDefinition(
@@ -105,7 +126,7 @@ function test(
                 $typeAnalysis = $argument->getTypeAnalysis();
                 if ($typeAnalysis) {
                     $hasAtLeastOneTypedArgument = true;
-                    $typeLength = strlen($typeAnalysis->getName());
+                    $typeLength = $this->getFullTypeLength($tokens, $typeAnalysis->getStartIndex());
                     if ($typeLength > $longestType) {
                         $longestType = $typeLength;
                     }
@@ -124,24 +145,24 @@ function test(
                     if ($this->configuration[self::C_VARIABLES] === true) {
                         $typeLen = 0;
                         if ($argument->getTypeAnalysis() !== null) {
-                            $typeLen = strlen($argument->getTypeAnalysis()->getName());
+                            $typeLen = $this->getFullTypeLength($tokens, $argument->getTypeAnalysis()->getStartIndex());
                         }
 
                         $appendix = str_repeat(' ', $longestType - $typeLen + (int)$hasAtLeastOneTypedArgument);
                         if ($argument->hasTypeAnalysis()) {
-                            $whitespace = $appendix;
+                            $whitespaceToken = $appendix;
                         } else {
-                            $whitespace = $this->whitespacesConfig->getLineEnding() . $argsIndent . $appendix;
+                            $whitespaceToken = $this->whitespacesConfig->getLineEnding() . $argsIndent . $appendix;
                         }
                     } else {
                         if ($argument->hasTypeAnalysis()) {
-                            $whitespace = ' ';
+                            $whitespaceToken = ' ';
                         } else {
-                            $whitespace = $this->whitespacesConfig->getLineEnding() . $argsIndent;
+                            $whitespaceToken = $this->whitespacesConfig->getLineEnding() . $argsIndent;
                         }
                     }
 
-                    $tokens->ensureWhitespaceAtIndex($whitespaceIndex, 0, $whitespace);
+                    $tokens->ensureWhitespaceAtIndex($whitespaceIndex, 0, $whitespaceToken);
                 }
 
                 if ($this->configuration[self::C_DEFAULTS] !== null) {
@@ -162,4 +183,28 @@ function test(
         }
     }
 
+    private function getFullTypeLength(Tokens $tokens, int $typeIndex): int {
+        /** @var \PhpCsFixer\Tokenizer\Token $typeToken */
+        $typeToken = $tokens[$typeIndex];
+        $typeLength = strlen($typeToken->getContent());
+
+        /** @var \PhpCsFixer\Tokenizer\Token $possiblyReadonlyToken */
+        $possiblyReadonlyToken = $tokens[$typeIndex - 2];
+        if ($possiblyReadonlyToken->isGivenKind($this->parameterModifiers)) {
+            /** @var \PhpCsFixer\Tokenizer\Token $whitespaceToken */
+            $whitespaceToken = $tokens[$typeIndex - 1];
+            $typeLength += strlen($possiblyReadonlyToken->getContent() . $whitespaceToken->getContent());
+        }
+
+        /** @var \PhpCsFixer\Tokenizer\Token $possiblyPromotionToken */
+        $possiblyPromotionToken = $tokens[$typeIndex - 4];
+        if ($possiblyPromotionToken->isGivenKind($this->parameterModifiers)) {
+            /** @var \PhpCsFixer\Tokenizer\Token $whitespaceToken */
+            $whitespaceToken = $tokens[$typeIndex - 3];
+            $typeLength += strlen($possiblyPromotionToken->getContent() . $whitespaceToken->getContent());
+        }
+
+        return $typeLength;
+    }
+
 }
diff --git a/tests/Fixer/FunctionNotation/AlignMultilineParametersFixerTest.php b/tests/Fixer/FunctionNotation/AlignMultilineParametersFixerTest.php
index 85a65ba..85f45e2 100644
--- a/tests/Fixer/FunctionNotation/AlignMultilineParametersFixerTest.php
+++ b/tests/Fixer/FunctionNotation/AlignMultilineParametersFixerTest.php
@@ -17,8 +17,8 @@ final class AlignMultilineParametersFixerTest extends AbstractFixerTestCase {
      */
     public function testBothTrue(string $expected, ?string $input = null): void {
         $this->fixer->configure([
-            'variables' => true,
-            'defaults' => true,
+            AlignMultilineParametersFixer::C_VARIABLES => true,
+            AlignMultilineParametersFixer::C_DEFAULTS => true,
         ]);
         $this->doTest($expected, $input);
     }
@@ -179,8 +179,8 @@ final class AlignMultilineParametersFixerTest extends AbstractFixerTestCase {
      */
     public function testBothFalse(string $expected, ?string $input = null): void {
         $this->fixer->configure([
-            'variables' => false,
-            'defaults' => false,
+            AlignMultilineParametersFixer::C_VARIABLES => false,
+            AlignMultilineParametersFixer::C_DEFAULTS => false,
         ]);
         $this->doTest($expected, $input);
     }
@@ -200,8 +200,8 @@ final class AlignMultilineParametersFixerTest extends AbstractFixerTestCase {
      */
     public function testBothNull(string $expected, ?string $input = null): void {
         $this->fixer->configure([
-            'variables' => null,
-            'defaults' => null,
+            AlignMultilineParametersFixer::C_VARIABLES => null,
+            AlignMultilineParametersFixer::C_DEFAULTS => null,
         ]);
         $this->doTest($expected, $input);
     }
@@ -212,6 +212,138 @@ final class AlignMultilineParametersFixerTest extends AbstractFixerTestCase {
         }
     }
 
+    /**
+     * @dataProvider provide80TrueCases
+     * @requires PHP 8.0
+     */
+    public function test80BothTrue(string $expected, ?string $input = null): void {
+        $this->fixer->configure([
+            AlignMultilineParametersFixer::C_VARIABLES => true,
+            AlignMultilineParametersFixer::C_DEFAULTS => true,
+        ]);
+        $this->doTest($expected, $input);
+    }
+
+    public function provide80TrueCases(): iterable {
+        yield 'constructor promotion, defaults' => [
+            '<?php
+            class Test {
+                public function __construct(
+                    public string  $string = "string",
+                    protected bool $bool   = true
+                ) {}
+            }
+            ',
+            '<?php
+            class Test {
+                public function __construct(
+                    public string $string = "string",
+                    protected bool $bool = true
+                ) {}
+            }
+            ',
+        ];
+    }
+
+    /**
+     * @dataProvider provideFalse80Cases
+     * @requires PHP 8.0
+     */
+    public function test80BothFalse(string $expected, ?string $input = null): void {
+        $this->fixer->configure([
+            AlignMultilineParametersFixer::C_VARIABLES => false,
+            AlignMultilineParametersFixer::C_DEFAULTS => false,
+        ]);
+        $this->doTest($expected, $input);
+    }
+
+    public function provideFalse80Cases(): iterable {
+        foreach ($this->provide80TrueCases() as $key => $case) {
+            if (isset($case[1])) {
+                yield $key => [$case[1], $case[0]];
+            } else {
+                yield $key => $case;
+            }
+        }
+    }
+
+    /**
+     * @dataProvider provide81TrueCases
+     * @requires PHP 8.1
+     */
+    public function test81BothTrue(string $expected, ?string $input = null): void {
+        $this->fixer->configure([
+            AlignMultilineParametersFixer::C_VARIABLES => true,
+            AlignMultilineParametersFixer::C_DEFAULTS => true,
+        ]);
+        $this->doTest($expected, $input);
+    }
+
+    public function provide81TrueCases(): iterable {
+        yield 'constructor promotion, readonly, defaults' => [
+            '<?php
+            class Test {
+                public function __construct(
+                    public readonly string  $string = "string",
+                    protected readonly bool $bool   = true
+                ) {}
+            }
+            ',
+            '<?php
+            class Test {
+                public function __construct(
+                    public readonly string $string = "string",
+                    protected readonly bool $bool = true
+                ) {}
+            }
+            ',
+        ];
+        yield 'partial constructor promotion, readonly, defaults' => [
+            '<?php
+            class Test {
+                public function __construct(
+                    readonly string $string = "string",
+                    int             $int    = 0,
+                    protected bool  $bool   = true,
+                                    $float  = 0.0,
+                ) {}
+            }
+            ',
+            '<?php
+            class Test {
+                public function __construct(
+                    readonly string $string = "string",
+                    int $int = 0,
+                    protected bool $bool = true,
+                    $float = 0.0,
+                ) {}
+            }
+            ',
+        ];
+    }
+
+    /**
+     * @dataProvider provideFalse81Cases
+     * @requires PHP 8.1
+     */
+    public function test81BothFalse(string $expected, ?string $input = null): void {
+        $this->fixer->configure([
+            AlignMultilineParametersFixer::C_VARIABLES => false,
+            AlignMultilineParametersFixer::C_DEFAULTS => false,
+        ]);
+        $this->doTest($expected, $input);
+    }
+
+    public function provideFalse81Cases(): iterable {
+        foreach ($this->provide81TrueCases() as $key => $case) {
+            if (isset($case[1])) {
+                yield $key => [$case[1], $case[0]];
+            } else {
+                yield $key => $case;
+            }
+        }
+    }
+
     protected function createFixer(): AbstractFixer {
         return new AlignMultilineParametersFixer();
     }