diff --git a/src/Api/Packages.php b/src/Api/Packages.php
index e8978b7..2108ee3 100644
--- a/src/Api/Packages.php
+++ b/src/Api/Packages.php
@@ -11,6 +11,9 @@
 
 use PrivatePackagist\ApiClient\Api\Packages\Artifacts;
 use PrivatePackagist\ApiClient\Exception\InvalidArgumentException;
+use PrivatePackagist\ApiClient\Payload\ArtifactPackageConfig;
+use PrivatePackagist\ApiClient\Payload\CustomPackageConfig;
+use PrivatePackagist\ApiClient\Payload\VcsPackageConfig;
 
 class Packages extends AbstractApi
 {
@@ -55,23 +58,25 @@ public function show($packageName)
         return $this->get(sprintf('/packages/%s/', $packageName));
     }
 
-    public function createVcsPackage($url, $credentialId = null, $type = 'vcs')
+    public function createVcsPackage($url, $credentialId = null, $type = 'vcs', $defaultSubrepositoryAccess = null)
     {
-        return $this->post('/packages/', ['repoType' => $type, 'repoUrl' => $url, 'credentials' => $credentialId]);
+        $data = new VcsPackageConfig($url, $credentialId, $type, $defaultSubrepositoryAccess);
+
+        return $this->post('/packages/', $data->toParameters());
     }
 
-    public function createCustomPackage($customJson, $credentialId = null)
+    public function createCustomPackage($customJson, $credentialId = null, $defaultSubrepositoryAccess = null)
     {
-        if (is_array($customJson) || is_object($customJson)) {
-            $customJson = json_encode($customJson);
-        }
+        $data = new CustomPackageConfig($customJson, $credentialId, $defaultSubrepositoryAccess);
 
-        return $this->post('/packages/', ['repoType' => 'package', 'repoConfig' => $customJson, 'credentials' => $credentialId]);
+        return $this->post('/packages/', $data->toParameters());
     }
 
-    public function createArtifactPackage(array $artifactPackageFileIds)
+    public function createArtifactPackage(array $artifactPackageFileIds, $defaultSubrepositoryAccess = null)
     {
-        return $this->post('/packages/', ['repoType' => 'artifact', 'artifactIds' => $artifactPackageFileIds]);
+        $data = new ArtifactPackageConfig($artifactPackageFileIds, $defaultSubrepositoryAccess);
+
+        return $this->post('/packages/', $data->toParameters());
     }
 
     /**
@@ -82,14 +87,18 @@ public function updateVcsPackage($packageName, $url, $credentialId = null)
         return $this->editVcsPackage($packageName, $url, $credentialId);
     }
 
-    public function editVcsPackage($packageName, $url, $credentialId = null, $type = 'vcs')
+    public function editVcsPackage($packageName, $url, $credentialId = null, $type = 'vcs', $defaultSubrepositoryAccess = null)
     {
-        return $this->put(sprintf('/packages/%s/', $packageName), ['repoType' => $type, 'repoUrl' => $url, 'credentials' => $credentialId]);
+        $data = new VcsPackageConfig($url, $credentialId, $type, $defaultSubrepositoryAccess);
+
+        return $this->put(sprintf('/packages/%s/', $packageName), $data->toParameters());
     }
 
-    public function editArtifactPackage($packageName, array $artifactPackageFileIds)
+    public function editArtifactPackage($packageName, array $artifactPackageFileIds, $defaultSubrepositoryAccess = null)
     {
-        return $this->put(sprintf('/packages/%s/', $packageName), ['repoType' => 'artifact', 'artifactIds' => $artifactPackageFileIds]);
+        $data = new ArtifactPackageConfig($artifactPackageFileIds, $defaultSubrepositoryAccess);
+
+        return $this->put(sprintf('/packages/%s/', $packageName), $data->toParameters());
     }
 
     /**
@@ -97,12 +106,14 @@ public function editArtifactPackage($packageName, array $artifactPackageFileIds)
      */
     public function updateCustomPackage($packageName, $customJson, $credentialId = null)
     {
-        return $this->editVcsPackage($packageName, $customJson, $credentialId);
+        return $this->editCustomPackage($packageName, $customJson, $credentialId);
     }
 
-    public function editCustomPackage($packageName, $customJson, $credentialId = null)
+    public function editCustomPackage($packageName, $customJson, $credentialId = null, $defaultSubrepositoryAccess = null)
     {
-        return $this->put(sprintf('/packages/%s/', $packageName), ['repoType' => 'package', 'repoConfig' => $customJson, 'credentials' => $credentialId]);
+        $data = new CustomPackageConfig($customJson, $credentialId, $defaultSubrepositoryAccess);
+
+        return $this->put(sprintf('/packages/%s/', $packageName), $data->toParameters());
     }
 
     public function remove($packageName)
diff --git a/src/Api/Subrepositories/Packages.php b/src/Api/Subrepositories/Packages.php
index c8480c0..b4bd36b 100644
--- a/src/Api/Subrepositories/Packages.php
+++ b/src/Api/Subrepositories/Packages.php
@@ -11,6 +11,8 @@
 
 use PrivatePackagist\ApiClient\Api\AbstractApi;
 use PrivatePackagist\ApiClient\Exception\InvalidArgumentException;
+use PrivatePackagist\ApiClient\Payload\CustomPackageConfig;
+use PrivatePackagist\ApiClient\Payload\VcsPackageConfig;
 
 class Packages extends AbstractApi
 {
@@ -28,28 +30,32 @@ public function show($subrepositoryName, $packageName)
         return $this->get(sprintf('/subrepositories/%s/packages/%s', $subrepositoryName, $packageName));
     }
 
-    public function createVcsPackage($subrepositoryName, $url, $credentialId = null, $type = 'vcs')
+    public function createVcsPackage($subrepositoryName, $url, $credentialId = null, $type = 'vcs', $defaultSubrepositoryAccess = null)
     {
-        return $this->post(sprintf('/subrepositories/%s/packages/', $subrepositoryName), ['repoType' => $type, 'repoUrl' => $url, 'credentials' => $credentialId]);
+        $data = new VcsPackageConfig($url, $credentialId, $type, $defaultSubrepositoryAccess);
+
+        return $this->post(sprintf('/subrepositories/%s/packages/', $subrepositoryName), $data->toParameters());
     }
 
-    public function createCustomPackage($subrepositoryName, $customJson, $credentialId = null)
+    public function createCustomPackage($subrepositoryName, $customJson, $credentialId = null, $defaultSubrepositoryAccess = null)
     {
-        if (is_array($customJson) || is_object($customJson)) {
-            $customJson = json_encode($customJson);
-        }
+        $data = new CustomPackageConfig($customJson, $credentialId, $defaultSubrepositoryAccess);
 
-        return $this->post(sprintf('/subrepositories/%s/packages/', $subrepositoryName), ['repoType' => 'package', 'repoConfig' => $customJson, 'credentials' => $credentialId]);
+        return $this->post(sprintf('/subrepositories/%s/packages/', $subrepositoryName), $data->toParameters());
     }
 
-    public function editVcsPackage($subrepositoryName, $packageName, $url, $credentialId = null, $type = 'vcs')
+    public function editVcsPackage($subrepositoryName, $packageName, $url, $credentialId = null, $type = 'vcs', $defaultSubrepositoryAccess = null)
     {
-        return $this->put(sprintf('/subrepositories/%s/packages/%s/', $subrepositoryName, $packageName), ['repoType' => $type, 'repoUrl' => $url, 'credentials' => $credentialId]);
+        $data = new VcsPackageConfig($url, $credentialId, $type, $defaultSubrepositoryAccess);
+
+        return $this->put(sprintf('/subrepositories/%s/packages/%s/', $subrepositoryName, $packageName), $data->toParameters());
     }
 
-    public function editCustomPackage($subrepositoryName, $packageName, $customJson, $credentialId = null)
+    public function editCustomPackage($subrepositoryName, $packageName, $customJson, $credentialId = null, $defaultSubrepositoryAccess = null)
     {
-        return $this->put(sprintf('/subrepositories/%s/packages/%s/', $subrepositoryName, $packageName), ['repoType' => 'package', 'repoConfig' => $customJson, 'credentials' => $credentialId]);
+        $data = new CustomPackageConfig($customJson, $credentialId, $defaultSubrepositoryAccess);
+
+        return $this->put(sprintf('/subrepositories/%s/packages/%s/', $subrepositoryName, $packageName), $data->toParameters());
     }
 
     public function remove($subrepositoryName, $packageName)
diff --git a/src/Payload/ArtifactPackageConfig.php b/src/Payload/ArtifactPackageConfig.php
new file mode 100644
index 0000000..9501685
--- /dev/null
+++ b/src/Payload/ArtifactPackageConfig.php
@@ -0,0 +1,42 @@
+<?php declare(strict_types=1);
+
+namespace PrivatePackagist\ApiClient\Payload;
+
+/**
+ * @internal
+ * @final
+ */
+class ArtifactPackageConfig
+{
+    /** @var int[] */
+    private $artifactPackageFileIds;
+    /** @var ?string */
+    private $defaultSubrepositoryAccess;
+
+    /**
+     * @param int[] $artifactPackageFileIds
+     * @param ?string $defaultSubrepositoryAccess
+     */
+    public function __construct(array $artifactPackageFileIds, $defaultSubrepositoryAccess)
+    {
+        $this->artifactPackageFileIds = $artifactPackageFileIds;
+        $this->defaultSubrepositoryAccess = $defaultSubrepositoryAccess;
+    }
+
+    /**
+     * @return array{repoType: string, artifactIds: int[], defaultSubrepositoryAccess?: string}
+     */
+    public function toParameters(): array
+    {
+        $data = [
+            'repoType' => 'artifact',
+            'artifactIds' => $this->artifactPackageFileIds,
+        ];
+
+        if ($this->defaultSubrepositoryAccess) {
+            $data['defaultSubrepositoryAccess'] = $this->defaultSubrepositoryAccess;
+        }
+
+        return $data;
+    }
+}
diff --git a/src/Payload/CustomPackageConfig.php b/src/Payload/CustomPackageConfig.php
new file mode 100644
index 0000000..0b54886
--- /dev/null
+++ b/src/Payload/CustomPackageConfig.php
@@ -0,0 +1,51 @@
+<?php declare(strict_types=1);
+
+namespace PrivatePackagist\ApiClient\Payload;
+
+/**
+ * @internal
+ * @final
+ */
+class CustomPackageConfig
+{
+    /** @var string */
+    private $customJson;
+    /** @var ?int */
+    private $credentialId;
+    /** @var ?string */
+    private $defaultSubrepositoryAccess;
+
+    /**
+     * @param string|array|object $customJson
+     * @param ?int $credentialId
+     * @param ?string $defaultSubrepositoryAccess
+     */
+    public function __construct($customJson, $credentialId, $defaultSubrepositoryAccess)
+    {
+        if (is_array($customJson) || is_object($customJson)) {
+            $customJson = json_encode($customJson);
+        }
+
+        $this->customJson = $customJson;
+        $this->credentialId = $credentialId;
+        $this->defaultSubrepositoryAccess = $defaultSubrepositoryAccess;
+    }
+
+    /**
+     * @return array{repoType: string, repoConfig: string, credentials: ?int, defaultSubrepositoryAccess?: string}
+     */
+    public function toParameters(): array
+    {
+        $data = [
+            'repoType' => 'package',
+            'repoConfig' => $this->customJson,
+            'credentials' => $this->credentialId,
+        ];
+
+        if ($this->defaultSubrepositoryAccess) {
+            $data['defaultSubrepositoryAccess'] = $this->defaultSubrepositoryAccess;
+        }
+
+        return $data;
+    }
+}
diff --git a/src/Payload/VcsPackageConfig.php b/src/Payload/VcsPackageConfig.php
new file mode 100644
index 0000000..5aa2eb7
--- /dev/null
+++ b/src/Payload/VcsPackageConfig.php
@@ -0,0 +1,51 @@
+<?php declare(strict_types=1);
+
+namespace PrivatePackagist\ApiClient\Payload;
+
+/**
+ * @internal
+ * @final
+ */
+class VcsPackageConfig
+{
+    /** @var string */
+    private $url;
+    /** @var ?int */
+    private $credentialId;
+    /** @var string */
+    private $type;
+    /** @var ?string */
+    private $defaultSubrepositoryAccess;
+
+    /**
+     * @param string $url
+     * @param ?int $credentialId
+     * @param string $type
+     * @param ?string $defaultSubrepositoryAccess
+     */
+    public function __construct($url, $credentialId, $type, $defaultSubrepositoryAccess)
+    {
+        $this->url = $url;
+        $this->credentialId = $credentialId;
+        $this->type = $type;
+        $this->defaultSubrepositoryAccess = $defaultSubrepositoryAccess;
+    }
+
+    /**
+     * @return array{repoType: string, repoUrl: string, credentials: ?int, defaultSubrepositoryAccess?: string}
+     */
+    public function toParameters(): array
+    {
+        $data = [
+            'repoType' => $this->type,
+            'repoUrl' => $this->url,
+            'credentials' => $this->credentialId,
+        ];
+
+        if ($this->defaultSubrepositoryAccess) {
+            $data['defaultSubrepositoryAccess'] = $this->defaultSubrepositoryAccess;
+        }
+
+        return $data;
+    }
+}
diff --git a/tests/Api/PackagesTest.php b/tests/Api/PackagesTest.php
index 0291c6d..8cc5dac 100644
--- a/tests/Api/PackagesTest.php
+++ b/tests/Api/PackagesTest.php
@@ -106,10 +106,27 @@ public function testCreateVcsPackage()
         $this->assertSame($expected, $api->createVcsPackage('localhost'));
     }
 
+    public function testCreateVcsPackageWithDefaultSubrepositoryAccess()
+    {
+        $expected = [
+            'id' => 'job-id',
+            'status' => 'queued',
+        ];
+
+        /** @var Packages&MockObject $api */
+        $api = $this->getApiMock();
+        $api->expects($this->once())
+            ->method('post')
+            ->with($this->equalTo('/packages/'), $this->equalTo(['repoType' => 'vcs', 'repoUrl' => 'localhost', 'credentials' => null, 'defaultSubrepositoryAccess' => 'no-access']))
+            ->willReturn($expected);
+
+        $this->assertSame($expected, $api->createVcsPackage('localhost', null, 'vcs', 'no-access'));
+    }
+
     /**
      * @dataProvider customProvider
      */
-    public function testCreateCustomPackage($customJson)
+    public function testCreateCustomPackage($customJson, $defaultSubrepositoryAccess, array $expectedPayload)
     {
         $expected = [
             'id' => 'job-id',
@@ -120,13 +137,23 @@ public function testCreateCustomPackage($customJson)
         $api = $this->getApiMock();
         $api->expects($this->once())
             ->method('post')
-            ->with($this->equalTo('/packages/'), $this->equalTo(['repoType' => 'package', 'repoConfig' => '{}', 'credentials' => null]))
+            ->with($this->equalTo('/packages/'), $this->equalTo($expectedPayload))
             ->willReturn($expected);
 
-        $this->assertSame($expected, $api->createCustomPackage($customJson));
+        $this->assertSame($expected, $api->createCustomPackage($customJson, null, $defaultSubrepositoryAccess));
     }
 
-    public function testCreateArtifactPackage()
+    public function customProvider()
+    {
+        return [
+            ['{}', null, ['repoType' => 'package', 'repoConfig' => '{}', 'credentials' => null]],
+            [new \stdClass(), null, ['repoType' => 'package', 'repoConfig' => '{}', 'credentials' => null]],
+            [[], null, ['repoType' => 'package', 'repoConfig' => '[]', 'credentials' => null]],
+            ['{}', 'no-access', ['repoType' => 'package', 'repoConfig' => '{}', 'credentials' => null, 'defaultSubrepositoryAccess' => 'no-access']],
+        ];
+    }
+
+    public function testCreateArtifactPackageWithDefaultSubrepositoryAccess()
     {
         $expected = [
             'id' => 'job-id',
@@ -137,18 +164,27 @@ public function testCreateArtifactPackage()
         $api = $this->getApiMock();
         $api->expects($this->once())
             ->method('post')
-            ->with($this->equalTo('/packages/'), $this->equalTo(['repoType' => 'artifact', 'artifactIds' => [42]]))
+            ->with($this->equalTo('/packages/'), $this->equalTo(['repoType' => 'artifact', 'artifactIds' => [42], 'defaultSubrepositoryAccess' => 'no-access']))
             ->willReturn($expected);
 
-        $this->assertSame($expected, $api->createArtifactPackage([42]));
+        $this->assertSame($expected, $api->createArtifactPackage([42], 'no-access'));
     }
 
-    public function customProvider()
+    public function testCreateArtifactPackage()
     {
-        return [
-            ['{}'],
-            [new \stdClass()],
+        $expected = [
+            'id' => 'job-id',
+            'status' => 'queued',
         ];
+
+        /** @var Packages&MockObject $api */
+        $api = $this->getApiMock();
+        $api->expects($this->once())
+            ->method('post')
+            ->with($this->equalTo('/packages/'), $this->equalTo(['repoType' => 'artifact', 'artifactIds' => [42]]))
+            ->willReturn($expected);
+
+        $this->assertSame($expected, $api->createArtifactPackage([42]));
     }
 
     public function testEditVcsPackage()