diff --git a/src/main/java/com/github/steveice10/mc/protocol/MinecraftProtocol.java b/src/main/java/com/github/steveice10/mc/protocol/MinecraftProtocol.java
index 21498653..1f076c99 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/MinecraftProtocol.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/MinecraftProtocol.java
@@ -6,6 +6,8 @@ import com.github.steveice10.mc.protocol.codec.MinecraftCodecHelper;
 import com.github.steveice10.mc.protocol.codec.PacketCodec;
 import com.github.steveice10.mc.protocol.codec.PacketStateCodec;
 import com.github.steveice10.mc.protocol.data.ProtocolState;
+import com.github.steveice10.opennbt.NBTIO;
+import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import com.github.steveice10.packetlib.Server;
 import com.github.steveice10.packetlib.Session;
 import com.github.steveice10.packetlib.codec.PacketCodecHelper;
@@ -19,17 +21,31 @@ import io.netty.buffer.ByteBuf;
 import lombok.Getter;
 import lombok.NonNull;
 import lombok.Setter;
+import org.jetbrains.annotations.Nullable;
 
+import java.io.DataInput;
+import java.io.DataInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.security.GeneralSecurityException;
 import java.security.Key;
+import java.util.Objects;
 import java.util.UUID;
+import java.util.zip.GZIPInputStream;
 
 /**
  * Implements the Minecraft protocol.
  */
 public class MinecraftProtocol extends PacketProtocol {
 
+    /**
+     * The network codec sent from the server to the client during {@link ProtocolState#CONFIGURATION}.
+     * Lazily loaded once when {@link #newServerSession(Server, Session)} is invoked,
+     * if {@link #isUseDefaultListeners()} is true.
+     */
+    @Nullable
+    private static CompoundTag DEFAULT_NETWORK_CODEC;
+
     /**
      * The codec used for the Minecraft protocol.
      */
@@ -156,7 +172,11 @@ public class MinecraftProtocol extends PacketProtocol {
         this.setState(ProtocolState.HANDSHAKE);
 
         if (this.useDefaultListeners) {
-            session.addListener(new ServerListener());
+            if (DEFAULT_NETWORK_CODEC == null) {
+                DEFAULT_NETWORK_CODEC = loadNetworkCodec();
+            }
+
+            session.addListener(new ServerListener(DEFAULT_NETWORK_CODEC));
         }
     }
 
@@ -231,4 +251,13 @@ public class MinecraftProtocol extends PacketProtocol {
     public PacketDefinition<?, ?> getClientboundDefinition(int id) {
         return this.stateCodec.getClientboundDefinition(id);
     }
+
+    public static CompoundTag loadNetworkCodec() {
+        try (InputStream inputStream = Objects.requireNonNull(MinecraftProtocol.class.getClassLoader().getResourceAsStream("networkCodec.nbt")) ;
+             DataInputStream stream = new DataInputStream(new GZIPInputStream(inputStream))) {
+            return (CompoundTag) NBTIO.readTag((DataInput) stream);
+        } catch (Exception e) {
+            throw new AssertionError("Unable to load network codec.", e);
+        }
+    }
 }
diff --git a/src/main/java/com/github/steveice10/mc/protocol/ServerListener.java b/src/main/java/com/github/steveice10/mc/protocol/ServerListener.java
index 0a0d5bcf..9144830d 100644
--- a/src/main/java/com/github/steveice10/mc/protocol/ServerListener.java
+++ b/src/main/java/com/github/steveice10/mc/protocol/ServerListener.java
@@ -27,7 +27,6 @@ import com.github.steveice10.mc.protocol.packet.status.clientbound.ClientboundPo
 import com.github.steveice10.mc.protocol.packet.status.clientbound.ClientboundStatusResponsePacket;
 import com.github.steveice10.mc.protocol.packet.status.serverbound.ServerboundPingRequestPacket;
 import com.github.steveice10.mc.protocol.packet.status.serverbound.ServerboundStatusRequestPacket;
-import com.github.steveice10.opennbt.NBTIO;
 import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
 import com.github.steveice10.packetlib.Session;
 import com.github.steveice10.packetlib.event.session.ConnectedEvent;
@@ -37,10 +36,6 @@ import com.github.steveice10.packetlib.packet.Packet;
 import net.kyori.adventure.text.Component;
 
 import javax.crypto.SecretKey;
-import java.io.DataInput;
-import java.io.DataInputStream;
-import java.io.IOException;
-import java.io.InputStream;
 import java.security.KeyPair;
 import java.security.KeyPairGenerator;
 import java.security.NoSuchAlgorithmException;
@@ -49,7 +44,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Random;
 import java.util.UUID;
-import java.util.zip.GZIPInputStream;
 
 /**
  * Handles initial login and status requests for servers.
@@ -71,13 +65,16 @@ public class ServerListener extends SessionAdapter {
         }
     }
 
+    private final CompoundTag networkCodec;
+
     private final byte[] challenge = new byte[4];
     private String username = "";
 
     private long lastPingTime = 0;
     private int lastPingId = 0;
 
-    public ServerListener() {
+    public ServerListener(CompoundTag networkCodec) {
+        this.networkCodec = networkCodec;
         new Random().nextBytes(this.challenge);
     }
 
@@ -132,7 +129,7 @@ public class ServerListener extends SessionAdapter {
                 new Thread(new UserAuthTask(session, key)).start();
             } else if (packet instanceof ServerboundLoginAcknowledgedPacket) {
                 ((MinecraftProtocol) session.getPacketProtocol()).setState(ProtocolState.CONFIGURATION);
-                session.send(new ClientboundRegistryDataPacket(loadNetworkCodec()));
+                session.send(new ClientboundRegistryDataPacket(networkCodec));
                 session.send(new ClientboundFinishConfigurationPacket());
             }
         } else if (protocol.getState() == ProtocolState.STATUS) {
@@ -254,14 +251,4 @@ public class ServerListener extends SessionAdapter {
             }
         }
     }
-
-    public static CompoundTag loadNetworkCodec() {
-        try (InputStream inputStream = ServerListener.class.getClassLoader().getResourceAsStream("networkCodec.nbt");
-             DataInputStream stream = new DataInputStream(new GZIPInputStream(inputStream))) {
-            return (CompoundTag) NBTIO.readTag((DataInput) stream);
-        } catch (IOException e) {
-            e.printStackTrace();
-            throw new AssertionError("Unable to load network codec.");
-        }
-    }
 }