diff --git a/gateway/api/gateway.api b/gateway/api/gateway.api
index 25ff7ab3bb01..4891edf17d6b 100644
--- a/gateway/api/gateway.api
+++ b/gateway/api/gateway.api
@@ -1011,12 +1011,17 @@ public final class dev/kord/gateway/GuildUpdate : dev/kord/gateway/DispatchEvent
 public final class dev/kord/gateway/Heartbeat : dev/kord/gateway/Event {
 	public static final field Companion Ldev/kord/gateway/Heartbeat$Companion;
 	public static final field NewCompanion Ldev/kord/gateway/Heartbeat$NewCompanion;
-	public fun <init> (J)V
-	public final fun component1 ()J
-	public final fun copy (J)Ldev/kord/gateway/Heartbeat;
+	public synthetic fun <init> (J)V
+	public fun <init> (Ljava/lang/Long;)V
+	public final synthetic fun component1 ()J
+	public final fun component1 ()Ljava/lang/Long;
+	public final synthetic fun copy (J)Ldev/kord/gateway/Heartbeat;
+	public final fun copy (Ljava/lang/Long;)Ldev/kord/gateway/Heartbeat;
 	public static synthetic fun copy$default (Ldev/kord/gateway/Heartbeat;JILjava/lang/Object;)Ldev/kord/gateway/Heartbeat;
+	public static synthetic fun copy$default (Ldev/kord/gateway/Heartbeat;Ljava/lang/Long;ILjava/lang/Object;)Ldev/kord/gateway/Heartbeat;
 	public fun equals (Ljava/lang/Object;)Z
-	public final fun getData ()J
+	public final synthetic fun getData ()J
+	public final fun getData ()Ljava/lang/Long;
 	public fun hashCode ()I
 	public fun toString ()Ljava/lang/String;
 }
diff --git a/gateway/api/gateway.klib.api b/gateway/api/gateway.klib.api
index 7b9f0fb7d31a..a3a0da74c31c 100644
--- a/gateway/api/gateway.klib.api
+++ b/gateway/api/gateway.klib.api
@@ -1237,12 +1237,17 @@ final class dev.kord.gateway/GuildUpdate : dev.kord.gateway/DispatchEvent { // d
 
 final class dev.kord.gateway/Heartbeat : dev.kord.gateway/Event { // dev.kord.gateway/Heartbeat|null[0]
     constructor <init>(kotlin/Long) // dev.kord.gateway/Heartbeat.<init>|<init>(kotlin.Long){}[0]
+    constructor <init>(kotlin/Long?) // dev.kord.gateway/Heartbeat.<init>|<init>(kotlin.Long?){}[0]
 
     final val data // dev.kord.gateway/Heartbeat.data|{}data[0]
-        final fun <get-data>(): kotlin/Long // dev.kord.gateway/Heartbeat.data.<get-data>|<get-data>(){}[0]
-
-    final fun component1(): kotlin/Long // dev.kord.gateway/Heartbeat.component1|component1(){}[0]
-    final fun copy(kotlin/Long = ...): dev.kord.gateway/Heartbeat // dev.kord.gateway/Heartbeat.copy|copy(kotlin.Long){}[0]
+        final fun <get-data>(): kotlin/Long? // dev.kord.gateway/Heartbeat.data.<get-data>|<get-data>(){}[0]
+    final val data_ // dev.kord.gateway/Heartbeat.data_|{}data_[0]
+        final fun <get-data_>(): kotlin/Long // dev.kord.gateway/Heartbeat.data_.<get-data_>|<get-data_>(){}[0]
+
+    final fun component1(): kotlin/Long? // dev.kord.gateway/Heartbeat.component1|component1(){}[0]
+    final fun component1_(): kotlin/Long // dev.kord.gateway/Heartbeat.component1_|component1_(){}[0]
+    final fun copy(kotlin/Long? = ...): dev.kord.gateway/Heartbeat // dev.kord.gateway/Heartbeat.copy|copy(kotlin.Long?){}[0]
+    final fun copy_(kotlin/Long = ...): dev.kord.gateway/Heartbeat // dev.kord.gateway/Heartbeat.copy_|copy_(kotlin.Long){}[0]
     final fun equals(kotlin/Any?): kotlin/Boolean // dev.kord.gateway/Heartbeat.equals|equals(kotlin.Any?){}[0]
     final fun hashCode(): kotlin/Int // dev.kord.gateway/Heartbeat.hashCode|hashCode(){}[0]
     final fun toString(): kotlin/String // dev.kord.gateway/Heartbeat.toString|toString(){}[0]
diff --git a/gateway/src/commonMain/kotlin/Event.kt b/gateway/src/commonMain/kotlin/Event.kt
index ee0467a8dbfa..bf7c4e5f93ec 100644
--- a/gateway/src/commonMain/kotlin/Event.kt
+++ b/gateway/src/commonMain/kotlin/Event.kt
@@ -7,6 +7,7 @@ import dev.kord.common.serialization.DurationInSeconds
 import io.github.oshai.kotlinlogging.KotlinLogging
 import kotlinx.datetime.Instant
 import kotlinx.serialization.*
+import kotlinx.serialization.builtins.nullable
 import kotlinx.serialization.builtins.serializer
 import kotlinx.serialization.descriptors.*
 import kotlinx.serialization.encoding.CompositeDecoder
@@ -16,6 +17,7 @@ import kotlinx.serialization.encoding.decodeStructure
 import kotlinx.serialization.json.JsonDecoder
 import kotlinx.serialization.json.JsonElement
 import kotlin.jvm.JvmField
+import kotlin.jvm.JvmName
 import kotlinx.serialization.DeserializationStrategy as KDeserializationStrategy
 
 private val jsonLogger = KotlinLogging.logger { }
@@ -288,13 +290,40 @@ public data class ReadyData(
 )
 
 @Serializable(with = Heartbeat.Serializer::class)
-public data class Heartbeat(val data: Long) : Event() {
+public data class Heartbeat(val data: Long?) : Event() {
     internal object Serializer : KSerializer<Heartbeat> {
-        override val descriptor = PrimitiveSerialDescriptor("dev.kord.gateway.Heartbeat", PrimitiveKind.LONG)
-        override fun serialize(encoder: Encoder, value: Heartbeat) = encoder.encodeLong(value.data)
-        override fun deserialize(decoder: Decoder) = Heartbeat(decoder.decodeLong())
+        private val delegate = Long.serializer().nullable
+
+        override val descriptor = PrimitiveSerialDescriptor("dev.kord.gateway.Heartbeat", PrimitiveKind.LONG).nullable
+
+        override fun serialize(encoder: Encoder, value: Heartbeat) =
+            encoder.encodeSerializableValue(delegate, value.data)
+
+        override fun deserialize(decoder: Decoder) = Heartbeat(decoder.decodeSerializableValue(delegate))
     }
 
+    @Deprecated("Binary compatibility, keep for some releases.", level = DeprecationLevel.HIDDEN)
+    public constructor(data: Long) : this(data as Long?)
+
+    @Suppress("PropertyName")
+    @Deprecated("Binary compatibility, keep for some releases.", level = DeprecationLevel.HIDDEN)
+    @get:JvmName("getData")
+    public val data_: Long
+        get() = data ?: throw NullPointerException("This heartbeat request contains a null sequence number")
+
+    @Suppress("FunctionName")
+    @Deprecated("Binary compatibility, keep for some releases.", level = DeprecationLevel.HIDDEN)
+    @JvmName("component1")
+    public fun component1_(): Long =
+        component1() ?: throw NullPointerException("This heartbeat request contains a null sequence number")
+
+    @Suppress("FunctionName")
+    @Deprecated("Binary compatibility, keep for some releases.", level = DeprecationLevel.HIDDEN)
+    @JvmName("copy")
+    public fun copy_(
+        data: Long = this.data ?: throw NullPointerException("This heartbeat request contains a null sequence number"),
+    ): Heartbeat = Heartbeat(data as Long?)
+
     public companion object {
         @Suppress("DEPRECATION_ERROR")
         @Deprecated(
diff --git a/gateway/src/commonTest/kotlin/json/SerializationTest.kt b/gateway/src/commonTest/kotlin/json/SerializationTest.kt
index 55f58df8395e..23d0712136bc 100644
--- a/gateway/src/commonTest/kotlin/json/SerializationTest.kt
+++ b/gateway/src/commonTest/kotlin/json/SerializationTest.kt
@@ -13,6 +13,7 @@ import kotlinx.serialization.MissingFieldException
 import kotlinx.serialization.json.Json
 import kotlinx.serialization.json.JsonNull
 import kotlin.js.JsName
+import kotlin.random.Random
 import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
@@ -167,6 +168,23 @@ class SerializationTest {
         }
     }
 
+    @Test
+    fun test_Heartbeat_Event_serialization() {
+        val sequenceNumbers = listOf(null, 0, -1, 1, Random.nextLong(), Long.MIN_VALUE, Long.MAX_VALUE)
+        sequenceNumbers.forEach { sequenceNumber ->
+            val heartbeat = Heartbeat(sequenceNumber)
+            val permutations = listOf(
+                jsonObjectPermutations("op" to "1", "d" to "$sequenceNumber"),
+                jsonObjectPermutations("op" to "1", "t" to "null", "d" to "$sequenceNumber"),
+                jsonObjectPermutations("op" to "1", "s" to "null", "d" to "$sequenceNumber"),
+                jsonObjectPermutations("op" to "1", "t" to "null", "s" to "null", "d" to "$sequenceNumber"),
+            ).flatten()
+            permutations.forEach { perm ->
+                assertEquals(heartbeat, Json.decodeFromString(Event.DeserializationStrategy, perm))
+            }
+        }
+    }
+
     @Test
     fun field_order_doesnt_matter() {
         val data = listOf(