diff --git a/Source/Core/Common/SFMLHelper.cpp b/Source/Core/Common/SFMLHelper.cpp
index 367bd93a9e..46b8ce836b 100644
--- a/Source/Core/Common/SFMLHelper.cpp
+++ b/Source/Core/Common/SFMLHelper.cpp
@@ -26,13 +26,8 @@ u32 PacketReadU32(sf::Packet& packet)
 
 u64 PacketReadU64(sf::Packet& packet)
 {
-  u32 low, high;
-  packet >> low >> high;
-  return low | (static_cast<u64>(high) << 32);
-}
-
-void PacketWriteU64(sf::Packet& packet, const u64 value)
-{
-  packet << static_cast<u32>(value) << static_cast<u32>(value >> 32);
+  sf::Uint64 value;
+  packet >> value;
+  return value;
 }
 }  // namespace Common
diff --git a/Source/Core/Common/SFMLHelper.h b/Source/Core/Common/SFMLHelper.h
index 459af6203b..46abb8d71f 100644
--- a/Source/Core/Common/SFMLHelper.h
+++ b/Source/Core/Common/SFMLHelper.h
@@ -19,5 +19,4 @@ struct BigEndianValue;
 u16 PacketReadU16(sf::Packet& packet);
 u32 PacketReadU32(sf::Packet& packet);
 u64 PacketReadU64(sf::Packet& packet);
-void PacketWriteU64(sf::Packet& packet, u64 value);
 }  // namespace Common
diff --git a/Source/Core/Core/NetPlayClient.cpp b/Source/Core/Core/NetPlayClient.cpp
index 3d02427c59..06f5be0d85 100644
--- a/Source/Core/Core/NetPlayClient.cpp
+++ b/Source/Core/Core/NetPlayClient.cpp
@@ -1769,11 +1769,11 @@ void NetPlayClient::SendTimeBase()
 
   if (netplay_client->m_timebase_frame % 60 == 0)
   {
-    u64 timebase = SystemTimers::GetFakeTimeBase();
+    const sf::Uint64 timebase = SystemTimers::GetFakeTimeBase();
 
     sf::Packet packet;
     packet << static_cast<MessageId>(NP_MSG_TIMEBASE);
-    Common::PacketWriteU64(packet, timebase);
+    packet << timebase;
     packet << netplay_client->m_timebase_frame;
 
     netplay_client->SendAsync(std::move(packet));
diff --git a/Source/Core/Core/NetPlayServer.cpp b/Source/Core/Core/NetPlayServer.cpp
index 18bf6eb378..aed13e093f 100644
--- a/Source/Core/Core/NetPlayServer.cpp
+++ b/Source/Core/Core/NetPlayServer.cpp
@@ -5,6 +5,7 @@
 #include "Core/NetPlayServer.h"
 
 #include <algorithm>
+#include <cinttypes>
 #include <cstddef>
 #include <cstdio>
 #include <memory>
@@ -989,7 +990,7 @@ bool NetPlayServer::StartGame()
 
   m_first_pad_status_received.fill(false);
 
-  const u64 initial_rtc = GetInitialNetPlayRTC();
+  const sf::Uint64 initial_rtc = GetInitialNetPlayRTC();
 
   const std::string region = SConfig::GetDirectoryForRegion(
       SConfig::ToGameCubeRegion(m_dialog->FindGameFile(m_selected_game)->GetRegion()));
@@ -1052,7 +1053,7 @@ bool NetPlayServer::StartGame()
   spac << m_settings.m_ArbitraryMipmapDetectionThreshold;
   spac << m_settings.m_EnableGPUTextureDecoding;
   spac << m_settings.m_StrictSettingsSync;
-  Common::PacketWriteU64(spac, initial_rtc);
+  spac << initial_rtc;
   spac << m_settings.m_SyncSaveData;
   spac << region;
 
@@ -1142,7 +1143,7 @@ bool NetPlayServer::SyncSaveData()
       else
       {
         // No file, so we'll say the size is 0
-        Common::PacketWriteU64(pac, 0);
+        pac << sf::Uint64{0};
       }
 
       SendAsyncToClients(std::move(pac));
@@ -1201,7 +1202,7 @@ bool NetPlayServer::SyncSaveData()
       pac << true;  // save exists
 
       // Header
-      Common::PacketWriteU64(pac, header->tid);
+      pac << sf::Uint64{header->tid};
       pac << header->banner_size << header->permissions << header->unk1;
       for (size_t i = 0; i < header->md5.size(); i++)
         pac << header->md5[i];
@@ -1215,7 +1216,7 @@ bool NetPlayServer::SyncSaveData()
           << bk_header->total_size;
       for (size_t i = 0; i < bk_header->unk3.size(); i++)
         pac << bk_header->unk3[i];
-      Common::PacketWriteU64(pac, bk_header->tid);
+      pac << sf::Uint64{bk_header->tid};
       for (size_t i = 0; i < bk_header->mac_address.size(); i++)
         pac << bk_header->mac_address[i];
 
@@ -1252,8 +1253,8 @@ bool NetPlayServer::CompressFileIntoPacket(const std::string& file_path, sf::Pac
     return false;
   }
 
-  const u64 size = file.GetSize();
-  Common::PacketWriteU64(packet, size);
+  const sf::Uint64 size = file.GetSize();
+  packet << size;
 
   if (size == 0)
     return true;
@@ -1314,8 +1315,8 @@ bool NetPlayServer::CompressFileIntoPacket(const std::string& file_path, sf::Pac
 
 bool NetPlayServer::CompressBufferIntoPacket(const std::vector<u8>& in_buffer, sf::Packet& packet)
 {
-  const u64 size = in_buffer.size();
-  Common::PacketWriteU64(packet, size);
+  const sf::Uint64 size = in_buffer.size();
+  packet << size;
 
   if (size == 0)
     return true;