diff --git a/Src/Notion.Client/Models/CustomEmoji.cs b/Src/Notion.Client/Models/CustomEmoji.cs
new file mode 100644
index 00000000..0f7a4c48
--- /dev/null
+++ b/Src/Notion.Client/Models/CustomEmoji.cs
@@ -0,0 +1,16 @@
+using Newtonsoft.Json;
+
+namespace Notion.Client
+{
+    public class CustomEmoji
+    {
+        [JsonProperty("id")]
+        public string Id { get; set; }
+
+        [JsonProperty("name")]
+        public string Name { get; set; }
+
+        [JsonProperty("url")]
+        public string Url { get; set; }
+    }
+}
diff --git a/Src/Notion.Client/Models/CustomEmojiObject.cs b/Src/Notion.Client/Models/CustomEmojiObject.cs
new file mode 100644
index 00000000..1faa4d74
--- /dev/null
+++ b/Src/Notion.Client/Models/CustomEmojiObject.cs
@@ -0,0 +1,13 @@
+using Newtonsoft.Json;
+
+namespace Notion.Client
+{
+    public class CustomEmojiObject : IPageIcon
+    {
+        [JsonProperty("custom_emoji")]
+        public CustomEmoji CustomEmoji { get; set; }
+
+        [JsonProperty("type")]
+        public string Type { get; set; }
+    }
+}
diff --git a/Src/Notion.Client/Models/Page/IPageIcon.cs b/Src/Notion.Client/Models/Page/IPageIcon.cs
index b9ebea56..5d692185 100644
--- a/Src/Notion.Client/Models/Page/IPageIcon.cs
+++ b/Src/Notion.Client/Models/Page/IPageIcon.cs
@@ -5,6 +5,7 @@ namespace Notion.Client
 {
     [JsonConverter(typeof(JsonSubtypes), "type")]
     [JsonSubtypes.KnownSubTypeAttribute(typeof(EmojiObject), "emoji")]
+    [JsonSubtypes.KnownSubTypeAttribute(typeof(CustomEmojiObject), "custom_emoji")]
     [JsonSubtypes.KnownSubTypeAttribute(typeof(FileObject), "file")]
     [JsonSubtypes.KnownSubTypeAttribute(typeof(FileObject), "external")]
     public interface IPageIcon
diff --git a/Src/Notion.Client/Models/PropertyValue/DateCustomConverter.cs b/Src/Notion.Client/Models/PropertyValue/DateCustomConverter.cs
new file mode 100644
index 00000000..6823c303
--- /dev/null
+++ b/Src/Notion.Client/Models/PropertyValue/DateCustomConverter.cs
@@ -0,0 +1,77 @@
+using System;
+using Newtonsoft.Json;
+
+namespace Notion.Client
+{
+    public class DateCustomConverter : JsonConverter<Date>
+    {
+        public override Date ReadJson(JsonReader reader, Type objectType, Date existingValue, bool hasExistingValue,
+            JsonSerializer serializer)
+        {
+            var jsonObject = serializer.Deserialize<DateJsonObject>(reader);
+
+            if (jsonObject == null)
+            {
+                return null;
+            }
+
+            var date = new Date
+            {
+                Start = ParseDateTime(jsonObject.Start, out bool includeTime),
+                End = ParseDateTime(jsonObject.End, out _),
+                TimeZone = jsonObject.TimeZone,
+                IncludeTime = includeTime,
+            };
+
+            return date;
+        }
+
+        public override void WriteJson(JsonWriter writer, Date value, JsonSerializer serializer)
+        {
+            if (value is null)
+            {
+                writer.WriteNull();
+
+                return;
+            }
+
+            writer.WriteStartObject();
+
+            if (value.Start.HasValue)
+            {
+                string startFormat = value.IncludeTime ? "yyyy-MM-ddTHH:mm:ss" : "yyyy-MM-dd";
+                writer.WritePropertyName("start");
+                writer.WriteValue(value.Start.Value.ToString(startFormat));
+            }
+
+            if (value.End.HasValue)
+            {
+                string endFormat = value.IncludeTime ? "yyyy-MM-ddTHH:mm:ss" : "yyyy-MM-dd";
+                writer.WritePropertyName("end");
+                writer.WriteValue(value.End.Value.ToString(endFormat));
+            }
+
+            if (!string.IsNullOrEmpty(value.TimeZone))
+            {
+                writer.WritePropertyName("time_zone");
+                writer.WriteValue(value.TimeZone);
+            }
+
+            writer.WriteEndObject();
+        }
+
+        private static DateTime? ParseDateTime(string dateTimeString, out bool includeTime)
+        {
+            includeTime = false;
+
+            if (string.IsNullOrEmpty(dateTimeString))
+            {
+                return null;
+            }
+
+            includeTime = dateTimeString.Contains("T") || dateTimeString.Contains(" ");
+
+            return DateTimeOffset.Parse(dateTimeString).UtcDateTime;
+        }
+    }
+}
diff --git a/Src/Notion.Client/Models/PropertyValue/DateJsonObject.cs b/Src/Notion.Client/Models/PropertyValue/DateJsonObject.cs
new file mode 100644
index 00000000..b33b58c7
--- /dev/null
+++ b/Src/Notion.Client/Models/PropertyValue/DateJsonObject.cs
@@ -0,0 +1,16 @@
+using Newtonsoft.Json;
+
+namespace Notion.Client
+{
+    internal class DateJsonObject
+    {
+        [JsonProperty("start")]
+        public string Start { get; set; }
+
+        [JsonProperty("end")]
+        public string End { get; set; }
+
+        [JsonProperty("time_zone")]
+        public string TimeZone { get; set; }
+    }
+}
diff --git a/Src/Notion.Client/Models/PropertyValue/DatePropertyValue.cs b/Src/Notion.Client/Models/PropertyValue/DatePropertyValue.cs
index 7467936b..b79707db 100644
--- a/Src/Notion.Client/Models/PropertyValue/DatePropertyValue.cs
+++ b/Src/Notion.Client/Models/PropertyValue/DatePropertyValue.cs
@@ -21,6 +21,7 @@ public class DatePropertyValue : PropertyValue
     /// <summary>
     ///     Date value object.
     /// </summary>
+    [JsonConverter(typeof(DateCustomConverter))]
     public class Date
     {
         /// <summary>
@@ -43,5 +44,10 @@ public class Date
         /// </summary>
         [JsonProperty("time_zone")]
         public string TimeZone { get; set; }
+
+        /// <summary>
+        ///     Whether to include time
+        /// </summary>
+        public bool IncludeTime { get; set; } = true;
     }
 }
diff --git a/Src/Notion.Client/Models/PropertyValue/RollupPropertyValue.cs b/Src/Notion.Client/Models/PropertyValue/RollupPropertyValue.cs
index 2eb104fb..92020c61 100644
--- a/Src/Notion.Client/Models/PropertyValue/RollupPropertyValue.cs
+++ b/Src/Notion.Client/Models/PropertyValue/RollupPropertyValue.cs
@@ -35,7 +35,7 @@ public class RollupValue
         ///     Date rollup property values contain a date property value.
         /// </summary>
         [JsonProperty("date")]
-        public DatePropertyValue Date { get; set; }
+        public Date Date { get; set; }
 
         /// <summary>
         ///     Array rollup property values contain an array of element objects.