diff --git a/src/Resources/CreditInvoice.php b/src/Resources/CreditInvoice.php
index c0b0adf..0bc104c 100644
--- a/src/Resources/CreditInvoice.php
+++ b/src/Resources/CreditInvoice.php
@@ -20,4 +20,9 @@ public function getResourceName(): string
     {
         return self::CONTROLLER_NAME;
     }
+
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
 }
diff --git a/src/Resources/Creditor.php b/src/Resources/Creditor.php
index 3f3064f..077476e 100644
--- a/src/Resources/Creditor.php
+++ b/src/Resources/Creditor.php
@@ -20,4 +20,9 @@ public function getResourceName(): string
     {
         return self::CONTROLLER_NAME;
     }
+
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
 }
diff --git a/src/Resources/Debtor.php b/src/Resources/Debtor.php
index 272e5a2..d7482eb 100644
--- a/src/Resources/Debtor.php
+++ b/src/Resources/Debtor.php
@@ -13,6 +13,11 @@ public function getResourceName(): string
         return self::CONTROLLER_NAME;
     }
 
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
+
     /**
      * @return array<mixed, string>
      */
diff --git a/src/Resources/Group.php b/src/Resources/Group.php
index ea57b4d..80461bb 100644
--- a/src/Resources/Group.php
+++ b/src/Resources/Group.php
@@ -10,4 +10,9 @@ public function getResourceName(): string
     {
         return self::CONTROLLER_NAME;
     }
+
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
 }
diff --git a/src/Resources/Invoice.php b/src/Resources/Invoice.php
index 20a7a12..89f743d 100644
--- a/src/Resources/Invoice.php
+++ b/src/Resources/Invoice.php
@@ -26,6 +26,11 @@ public function getResourceName(): string
         return self::CONTROLLER_NAME;
     }
 
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
+
     /**
      * @param  array<string, mixed>  $params
      * @return array<string, mixed>
diff --git a/src/Resources/Product.php b/src/Resources/Product.php
index 46ea99c..36c00f8 100644
--- a/src/Resources/Product.php
+++ b/src/Resources/Product.php
@@ -10,4 +10,9 @@ public function getResourceName(): string
     {
         return self::CONTROLLER_NAME;
     }
+
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
 }
diff --git a/src/Resources/Resource.php b/src/Resources/Resource.php
index 13a8f00..e19a93c 100644
--- a/src/Resources/Resource.php
+++ b/src/Resources/Resource.php
@@ -2,6 +2,7 @@
 
 namespace Vormkracht10\WeFact\Resources;
 
+use Exception;
 use GuzzleHttp\Client;
 use GuzzleHttp\Exception\BadResponseException;
 use GuzzleHttp\Exception\ClientException;
@@ -40,6 +41,64 @@ public function list(array $params = []): array
         );
     }
 
+    /**
+     * @return array<string, mixed>
+     *
+     * @throws ClientException|ServerException|BadResponseException|JsonException
+     */
+    public function listAll(int $offset = 0, int $perPage = 1000): array
+    {
+        // Rate limit the requests to prevent IP blocking.
+        $limitPerSecond = 300 / 60; // Per minute / seconds
+        $calls = 1;
+
+        $data = [];
+
+        $pluralResourceName = $this->getPluralResourceName();
+
+        try {
+            $result = $this->list(params: [
+                'limit' => $perPage,
+                'offset' => $offset,
+            ]
+            );
+        } catch (Exception $e) {
+            throw $e;
+        }
+
+        foreach ($result[$pluralResourceName] as $index => $item) {
+            $calls++;
+
+            if ($calls % $limitPerSecond == 0) {
+                sleep(1);
+            }
+
+            try {
+                $resultItem = $this->show([
+                    'Identifier' => $item['Identifier'],
+                ]);
+            } catch (Exception $e) {
+                throw $e;
+            }
+
+            if (is_array($resultItem) && isset($resultItem[$this->getResourceName()])) {
+                $result[$pluralResourceName][$index] = $resultItem[$this->getResourceName()];
+            } else {
+                // Handle the case where $resultItem is not an array or does not contain the expected resource name.
+                continue;
+            }
+        }
+
+        $data = array_merge($data, $result[$pluralResourceName] ?? []);
+
+        if ($result['currentresults'] >= $perPage) {
+            $offset += $perPage;
+            $data = array_merge($data, $this->listAll($offset, $perPage));
+        }
+
+        return $data;
+    }
+
     /**
      * @param  array<string, mixed>  $params
      * @return array<string, mixed>|MethodNotAvailableException|ClientException|ServerException|BadResponseException|JsonException
@@ -109,4 +168,6 @@ public function delete(array $params = []): array|MethodNotAvailableException|Cl
     }
 
     abstract public function getResourceName(): string;
+
+    abstract public function getPluralResourceName(): string;
 }
diff --git a/src/Resources/Settings/CostCategory.php b/src/Resources/Settings/CostCategory.php
index 3fafb51..c76db16 100644
--- a/src/Resources/Settings/CostCategory.php
+++ b/src/Resources/Settings/CostCategory.php
@@ -15,13 +15,18 @@ class CostCategory extends Resource
 {
     use Request;
 
-    final public const CONTROLLER_NAME = 'settings';
+    final public const CONTROLLER_NAME = 'costcategory';
 
     public function getResourceName(): string
     {
         return self::CONTROLLER_NAME;
     }
 
+    public function getPluralResourceName(): string
+    {
+        return 'costcategories';
+    }
+
     /**
      * @param  array<string, mixed>  $params
      * @return array<string, mixed>
diff --git a/src/Resources/Settings/Settings.php b/src/Resources/Settings/Settings.php
index caa8dca..54245a8 100644
--- a/src/Resources/Settings/Settings.php
+++ b/src/Resources/Settings/Settings.php
@@ -18,6 +18,11 @@ public function getResourceName(): string
         return self::CONTROLLER_NAME;
     }
 
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME;
+    }
+
     /**
      * @return array<mixed, string>
      */
diff --git a/src/Resources/Subscription.php b/src/Resources/Subscription.php
index 1d0da8c..29d62a5 100644
--- a/src/Resources/Subscription.php
+++ b/src/Resources/Subscription.php
@@ -18,6 +18,11 @@ public function getResourceName(): string
         return self::CONTROLLER_NAME;
     }
 
+    public function getPluralResourceName(): string
+    {
+        return self::CONTROLLER_NAME.'s';
+    }
+
     /**
      * @return array<string, mixed>
      *