diff --git a/Anthropic.SDK.Tests/CacheControlTests.cs b/Anthropic.SDK.Tests/CacheControlTests.cs
index 6719b29..ba8f364 100644
--- a/Anthropic.SDK.Tests/CacheControlTests.cs
+++ b/Anthropic.SDK.Tests/CacheControlTests.cs
@@ -236,6 +236,11 @@ public async Task TestCacheControlStreaming()
             Assert.IsTrue(messageResponses.First().StreamStartMessage.Usage.CacheCreationInputTokens > 0 ||
                           messageResponses.First().StreamStartMessage.Usage.CacheReadInputTokens > 0);
 
+            if (messageResponses.First().StreamStartMessage.Usage.CacheCreationInputTokens > 0)
+            {
+                Assert.IsTrue(messageResponses.First().StreamStartMessage.Usage.CacheCreation.Ephemeral5mInputTokens > 0);
+            }
+
             messages.Add(new Message(messageResponses));
             messages.Add(new Message(RoleType.User, "Who is the main character and how old is he?"));
 
@@ -487,7 +492,11 @@ public async Task TestCacheControlOfAssistantMessages()
             var systemMessages = new List<SystemMessage>()
             {
                 new SystemMessage("You are an expert at analyzing literary texts."),
-                new SystemMessage(content, new CacheControl() { Type = CacheControlType.ephemeral })
+                new SystemMessage(content, new CacheControl()
+                {
+                    Type = CacheControlType.ephemeral,
+                    TTL = CacheDuration.OneHour,
+                })
             };
             var parameters = new MessageParameters()
             {
@@ -505,7 +514,11 @@ public async Task TestCacheControlOfAssistantMessages()
             Assert.IsTrue(res.Usage.CacheCreationInputTokens > 0 || res.Usage.CacheReadInputTokens > 0);
 
             //try caching an assistant message
-            res.Message.Content.First().CacheControl = new CacheControl() { Type = CacheControlType.ephemeral };
+            res.Message.Content.First().CacheControl = new CacheControl()
+            {
+                Type = CacheControlType.ephemeral,
+                TTL = CacheDuration.OneHour,
+            };
 
             messages.Add(res.Message);
             messages.Add(new Message(RoleType.User, "Who is the main character and how old is he?"));
@@ -513,7 +526,8 @@ public async Task TestCacheControlOfAssistantMessages()
             var res2 = await client.Messages.GetClaudeMessageAsync(parameters);
 
             Assert.IsTrue(res2.Usage.CacheReadInputTokens > 0);
-
+            Assert.IsNotNull(res2.Usage.CacheCreation);
+            Assert.IsTrue(res2.Usage.CacheCreation.Ephemeral1hInputTokens > 0);
             Assert.IsNotNull(res2.Message.ToString());
 
             //message 3
diff --git a/Anthropic.SDK.Tests/DocumentTests.cs b/Anthropic.SDK.Tests/DocumentTests.cs
index dea21e3..b84381a 100644
--- a/Anthropic.SDK.Tests/DocumentTests.cs
+++ b/Anthropic.SDK.Tests/DocumentTests.cs
@@ -1,10 +1,4 @@
-using System;
-using System.Collections.Generic;
-using System.Diagnostics;
-using System.Linq;
-using System.Reflection;
-using System.Text;
-using System.Threading.Tasks;
+using System.Reflection;
 using Anthropic.SDK.Constants;
 using Anthropic.SDK.Messaging;
 
@@ -41,7 +35,8 @@ public async Task TestPDF()
                     },
                     CacheControl = new CacheControl()
                     {
-                        Type = CacheControlType.ephemeral
+                        Type = CacheControlType.ephemeral,
+                        TTL = CacheDuration.FiveMinutes,
                     }
                 }),
                 new Message(RoleType.User, "Which model has the highest human preference win rates across each use-case?"),
@@ -60,8 +55,11 @@ public async Task TestPDF()
             
             Assert.IsNotNull(res.FirstMessage.ToString());
             Assert.IsTrue(res.Usage.CacheCreationInputTokens > 0 || res.Usage.CacheReadInputTokens > 0);
-
-            
+            if (res.Usage.CacheCreationInputTokens > 0)
+            {
+                Assert.IsNotNull(res.Usage.CacheCreation);
+                Assert.IsTrue(res.Usage.CacheCreation.Ephemeral5mInputTokens > 0);
+            }
         }
 
         [TestMethod]
diff --git a/Anthropic.SDK/Messaging/CacheControl.cs b/Anthropic.SDK/Messaging/CacheControl.cs
index 35cb195..e915474 100644
--- a/Anthropic.SDK/Messaging/CacheControl.cs
+++ b/Anthropic.SDK/Messaging/CacheControl.cs
@@ -6,6 +6,14 @@ public class CacheControl
 {
     [JsonPropertyName("type")]
     public CacheControlType Type { get; set; }
+
+    /// <summary>
+    /// The duration to cache.
+    /// Supported values are <see cref="CacheDuration5Minutes"/> or <see cref="CacheDuration1Hour"/>
+    /// </summary>
+    [JsonPropertyName("ttl")]
+    [JsonConverter(typeof(CacheDurationConverter))]
+    public CacheDuration TTL { get; set; }
 }
 
 [JsonConverter(typeof(JsonStringEnumConverter))]
diff --git a/Anthropic.SDK/Messaging/CacheDurationConverter.cs b/Anthropic.SDK/Messaging/CacheDurationConverter.cs
new file mode 100644
index 0000000..702c3eb
--- /dev/null
+++ b/Anthropic.SDK/Messaging/CacheDurationConverter.cs
@@ -0,0 +1,36 @@
+using System;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace Anthropic.SDK.Messaging;
+
+public enum CacheDuration
+{
+    FiveMinutes,
+    OneHour
+}
+
+public class CacheDurationConverter : JsonConverter<CacheDuration>
+{
+    public override CacheDuration Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        string? value = reader.GetString();
+        return value switch
+        {
+            "5m" => CacheDuration.FiveMinutes,
+            "1h" => CacheDuration.OneHour,
+            _ => throw new JsonException($"Invalid cache duration: {value}")
+        };
+    }
+
+    public override void Write(Utf8JsonWriter writer, CacheDuration value, JsonSerializerOptions options)
+    {
+        string str = value switch
+        {
+            CacheDuration.FiveMinutes => "5m",
+            CacheDuration.OneHour => "1h",
+            _ => throw new JsonException($"Invalid cache duration enum: {value}")
+        };
+        writer.WriteStringValue(str);
+    }
+}
\ No newline at end of file
diff --git a/Anthropic.SDK/Messaging/MessageResponse.cs b/Anthropic.SDK/Messaging/MessageResponse.cs
index fa28d8e..8eb7aed 100644
--- a/Anthropic.SDK/Messaging/MessageResponse.cs
+++ b/Anthropic.SDK/Messaging/MessageResponse.cs
@@ -165,6 +165,18 @@ public class Usage
 
         [JsonPropertyName("server_tool_use")]
         public ServerToolUse ServerToolUse { get; set; }
+        
+        [JsonPropertyName("cache_creation")]
+        public CacheCreation CacheCreation { get; set; }
+    }
+
+    public class CacheCreation
+    {
+        [JsonPropertyName("ephemeral_5m_input_tokens")]
+        public int? Ephemeral5mInputTokens { get; set; }
+        
+        [JsonPropertyName("ephemeral_1h_input_tokens")]
+        public int? Ephemeral1hInputTokens { get; set; }
     }
 
     public class ServerToolUse