diff --git a/src/Suite/Api/Client.php b/src/Suite/Api/Client.php
index 28b290a..78833be 100644
--- a/src/Suite/Api/Client.php
+++ b/src/Suite/Api/Client.php
@@ -9,7 +9,6 @@
 use GuzzleHttp\Handler\CurlHandler;
 use GuzzleHttp\HandlerStack;
 use GuzzleHttp\Middleware;
-use GuzzleHttp\TransferStats;
 use Psr\Http\Message\RequestInterface;
 use Psr\Log\LoggerInterface;
 use Suite\Api\Middleware\Retry;
@@ -77,7 +76,7 @@ public function get(string $url, array $parameters = array())
     {
         $method = 'GET';
         $requestBody = '';
-        $fullUrl = $this->buildUrlWithParameters($url, $parameters);
+        $fullUrl = QueryStringAppender::appendParamsToUrl($url, $parameters);
         $headers = $this->getHeaders($fullUrl, $method, $requestBody);
         return $this->executeRequest($this->createRequest($method, $fullUrl, $headers, $requestBody));
     }
@@ -157,21 +156,4 @@ private function createRequest($method, $url, $headers, $requestBody)
     {
         return $this->requestFactory->createRequest($method, $url, $headers, $requestBody);
     }
-
-    /**
-     * @param string $url
-     * @param array $data
-     * @return string
-     */
-    private function buildUrlWithParameters(string $url, array $data): string
-    {
-        if (!empty($data))
-        {
-            return $url . '?' . http_build_query($data);
-        }
-        else
-        {
-            return $url;
-        }
-    }
 }
diff --git a/src/Suite/Api/ContactList.php b/src/Suite/Api/ContactList.php
index 56175fd..e4dc6e9 100644
--- a/src/Suite/Api/ContactList.php
+++ b/src/Suite/Api/ContactList.php
@@ -119,10 +119,10 @@ public function getContactsOfList(int $customerId, int $contactListId, int $limi
         }
     }
 
-    public function getContactIdsInList(int $customerId, int $contactListId, int $limit = null, string $skipToken = null)
+    public function getContactIdsInList(int $customerId, int $contactListId, int $top = null, string $skiptoken = null): array
     {
         try {
-            $response = $this->apiClient->get($this->endPoints->contactIdsInList($customerId, $contactListId, $limit, $skipToken));
+            $response = $this->apiClient->get($this->endPoints->contactIdsInList($customerId, $contactListId, $top, $skiptoken));
             return $response['data'] ?? [];
         } catch (Error $error) {
             throw new RequestFailed('Could not fetch contact ids: ' . $error->getMessage(), $error->getCode(), $error);
@@ -131,7 +131,7 @@ public function getContactIdsInList(int $customerId, int $contactListId, int $li
 
     public function getListChunkIterator(int $customerId, int $contactListId, int $chunkSize = 10000) : iterable
     {
-        $next = $this->endPoints->contactIdsInList($customerId, $contactListId, $chunkSize, 'first batch');
+        $next = $this->endPoints->contactIdsInList($customerId, $contactListId, $chunkSize);
         try {
             do {
                 ['value' => $value, 'next' => $next] = $this->apiClient->get($next)['data'];
diff --git a/src/Suite/Api/ContactListEndPoints.php b/src/Suite/Api/ContactListEndPoints.php
index 936fd2a..1eebffc 100644
--- a/src/Suite/Api/ContactListEndPoints.php
+++ b/src/Suite/Api/ContactListEndPoints.php
@@ -44,13 +44,15 @@ public function contactsOfList(int $customerId, int $contactListId, int $limit,
         return $this->baseUrl($customerId) . "/{$contactListId}/contacts/?limit={$limit}&offset={$offset}";
     }
 
-    public function contactIdsInList(int $customerId, int $contactListId, int $limit = null, string $skipToken = null)
-    {
-        $result = $this->baseUrl($customerId) . "/{$contactListId}/contactIds";
-        if (null !== $limit && null !== $skipToken) {
-            $result .= "?\$top={$limit}&\$skiptoken={$skipToken}";
-        }
-        return $result;
+    public function contactIdsInList(int $customerId, int $contactListId, int $top = null, int $skiptoken = null): string
+    {
+        return QueryStringAppender::appendParamsToUrl(
+            $this->baseUrl($customerId) . "/{$contactListId}/contactIds",
+            array_filter(
+                ['$top' => $top, '$skiptoken' => $skiptoken],
+                fn ($value) => $value !== null
+            )
+        );
     }
 
     public function deleteContactsFromList(int $customerId, int $contactListId): string
diff --git a/src/Suite/Api/QueryStringAppender.php b/src/Suite/Api/QueryStringAppender.php
new file mode 100644
index 0000000..5194b96
--- /dev/null
+++ b/src/Suite/Api/QueryStringAppender.php
@@ -0,0 +1,11 @@
+<?php
+
+namespace Suite\Api;
+
+class QueryStringAppender
+{
+    public static function appendParamsToUrl(string $url, array $data): string
+    {
+        return $url . (empty($data) ? '' : '?' . http_build_query($data));
+    }
+}
\ No newline at end of file
diff --git a/test/helper/ApiStub.php b/test/helper/ApiStub.php
index 159089f..7c8b63e 100644
--- a/test/helper/ApiStub.php
+++ b/test/helper/ApiStub.php
@@ -56,11 +56,11 @@ public static function setUp()
             return match ($contactListId) {
                 (string) self::LIST_ID_FOR_EMPTY_LIST => new Response(self::success('{"value":[],"next":null}')),
                 (string) self::LIST_ID_FOR_LIST_WITH_SINGLE_CHUNK => new Response(self::success('{"value":[1,2,3],"next":null}')),
-                (string) self::LIST_ID_FOR_LIST_WITH_MULTIPLE_CHUNKS => match ($request->query->get('$skiptoken')) {
-                    'first batch' => new Response(self::success('{"value":[1,2,3],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=second%20batch"}')),
-                    'second batch' => new Response(self::success('{"value":[4,5,6],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=third%20batch"}')),
-                    'third batch' => new Response(self::success('{"value":[7,8,9],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=fourth%20batch"}')),
-                    'fourth batch' => new Response(self::success('{"value":[10,11],"next":null}')),
+                (string) self::LIST_ID_FOR_LIST_WITH_MULTIPLE_CHUNKS => match ($request->query->get('$skiptoken') ?? '0') {
+                    '0' => new Response(self::success('{"value":[1,2,3],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=1"}')),
+                    '1' => new Response(self::success('{"value":[4,5,6],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=2"}')),
+                    '2' => new Response(self::success('{"value":[7,8,9],"next":"http://localhost:7984/'.$customerId.'/contactlist/'.$contactListId.'/contactIds?$skiptoken=3"}')),
+                    '3' => new Response(self::success('{"value":[10,11],"next":null}')),
                 },
                 (string) self::LIST_ID_FOR_WRONG_RESPONSE => new Response(self::error('invalid response format')),
                 default => new Response(self::error('contact list not found'), 404),
diff --git a/test/unit/Suite/Api/ContactListTest.php b/test/unit/Suite/Api/ContactListTest.php
index 70b4c21..2b293e2 100644
--- a/test/unit/Suite/Api/ContactListTest.php
+++ b/test/unit/Suite/Api/ContactListTest.php
@@ -262,7 +262,7 @@ public function getContactIdsInList_CalledWithProperUrlAndParams_ApiResponseConv
         $response = ['value' => [1, 2, 3], 'next' => null];
         $this->apiClient
             ->method('get')
-            ->with("api_base_url/$this->customerId/contactlist/$this->contactListId/contactIds?\$top=1&\$skiptoken=1")
+            ->with("api_base_url/$this->customerId/contactlist/$this->contactListId/contactIds?%24top=1&%24skiptoken=1")
             ->willReturn($this->apiSuccess($response));
 
         $result = $this->listService->getContactIdsInList($this->customerId, $this->contactListId, 1, 1);
@@ -333,7 +333,7 @@ public function getContactListChunkIterator_ListFitsInSingleChunk_ContactIdsRetu
     {
         $chunkSize = 3;
         $this->apiClient->expects($this->once())->method('get')
-            ->with("api_base_url/$this->customerId/contactlist/654321/contactIds?\$top=3&\$skiptoken=first batch")
+            ->with("api_base_url/$this->customerId/contactlist/$this->contactListId/contactIds?%24top=3")
             ->willReturn(
                 $this->apiSuccess(['value' => [1, 2, 3], 'next' => null])
             );