diff --git a/src/ModernHttpClient/Android/NativeCookieHandler.cs b/src/ModernHttpClient/Android/NativeCookieHandler.cs
index 7438987..674412f 100644
--- a/src/ModernHttpClient/Android/NativeCookieHandler.cs
+++ b/src/ModernHttpClient/Android/NativeCookieHandler.cs
@@ -21,7 +21,7 @@ public void SetCookies(IEnumerable<Cookie> cookies)
             }
         }
             
-        public List<Cookie> Cookies {
+        public IReadOnlyList<Cookie> Cookies {
             get {
                 return cookieManager.CookieStore.Cookies
                     .Select(ToNetCookie)
diff --git a/src/ModernHttpClient/Facades.cs b/src/ModernHttpClient/Facades.cs
index 114b221..5b30d9a 100644
--- a/src/ModernHttpClient/Facades.cs
+++ b/src/ModernHttpClient/Facades.cs
@@ -77,7 +77,7 @@ public void SetCookies(IEnumerable<Cookie> cookies)
             throw new Exception(wrongVersion);
         }
 
-        public List<Cookie> Cookies {
+        public IReadOnlyList<Cookie> Cookies {
             get { throw new Exception(wrongVersion); }
         }
     }
diff --git a/src/ModernHttpClient/iOS/NativeCookieHandler.cs b/src/ModernHttpClient/iOS/NativeCookieHandler.cs
index 3ab5409..7855b26 100644
--- a/src/ModernHttpClient/iOS/NativeCookieHandler.cs
+++ b/src/ModernHttpClient/iOS/NativeCookieHandler.cs
@@ -19,7 +19,7 @@ public void SetCookies(IEnumerable<Cookie> cookies)
             }
         }
 
-        public List<Cookie> Cookies {
+        public IReadOnlyList<Cookie> Cookies {
             get {
                 return NSHttpCookieStorage.SharedStorage.Cookies
                     .Select(ToNetCookie)