diff --git a/src/cargotype.cpp b/src/cargotype.cpp
index 72364e361b..f65e6f9186 100644
--- a/src/cargotype.cpp
+++ b/src/cargotype.cpp
@@ -19,8 +19,6 @@
 #include "table/strings.h"
 #include "table/cargo_const.h"
 
-#include <sstream>
-
 #include "safeguards.h"
 
 CargoSpec CargoSpec::array[NUM_CARGO];
diff --git a/src/console_cmds.cpp b/src/console_cmds.cpp
index 9ccc3a834e..ef863cc8c5 100644
--- a/src/console_cmds.cpp
+++ b/src/console_cmds.cpp
@@ -45,8 +45,6 @@
 #include "company_cmd.h"
 #include "misc_cmd.h"
 
-#include <sstream>
-
 #include "table/strings.h"
 
 #include "safeguards.h"
diff --git a/src/driver.cpp b/src/driver.cpp
index 28dec081f4..c790c9ebbb 100644
--- a/src/driver.cpp
+++ b/src/driver.cpp
@@ -17,7 +17,6 @@
 #include "video/video_driver.hpp"
 #include "string_func.h"
 #include "fileio_func.h"
-#include <sstream>
 
 #include "table/strings.h"
 
diff --git a/src/fileio.cpp b/src/fileio.cpp
index 299e6cca18..3d05b2a3c5 100644
--- a/src/fileio.cpp
+++ b/src/fileio.cpp
@@ -25,7 +25,6 @@
 #endif
 #include <charconv>
 #include <sys/stat.h>
-#include <sstream>
 #include <filesystem>
 
 #include "safeguards.h"
diff --git a/src/misc/dbg_helpers.cpp b/src/misc/dbg_helpers.cpp
index b2e743c7ea..647510ebd7 100644
--- a/src/misc/dbg_helpers.cpp
+++ b/src/misc/dbg_helpers.cpp
@@ -11,9 +11,6 @@
 #include "../rail_map.h"
 #include "dbg_helpers.h"
 
-#include <sstream>
-#include <iomanip>
-
 #include "../safeguards.h"
 
 /** Trackdir & TrackdirBits short names. */
@@ -62,10 +59,7 @@ std::string ValueStr(SignalType t)
 /** Translate TileIndex into string. */
 std::string TileStr(TileIndex tile)
 {
-	std::stringstream ss;
-	ss << "0x" << std::setfill('0') << std::setw(4) << std::hex << tile.base(); // 0x%04X
-	ss << " (" << TileX(tile) << ", " << TileY(tile) << ")";
-	return ss.str();
+	return fmt::format("0x{:04X} ({}, {})", tile.base(), TileX(tile), TileY(tile));
 }
 
 /**
diff --git a/src/misc_gui.cpp b/src/misc_gui.cpp
index 68c4e5c4ff..bae49d57f3 100644
--- a/src/misc_gui.cpp
+++ b/src/misc_gui.cpp
@@ -36,9 +36,6 @@
 
 #include "table/strings.h"
 
-#include <sstream>
-#include <iomanip>
-
 #include "safeguards.h"
 
 /** Method to open the OSK. */
diff --git a/src/network/network.cpp b/src/network/network.cpp
index 87500f5411..de11f48eef 100644
--- a/src/network/network.cpp
+++ b/src/network/network.cpp
@@ -41,8 +41,6 @@
 #	include "../fileio_func.h"
 #endif
 #include <charconv>
-#include <sstream>
-#include <iomanip>
 
 #include "table/strings.h"
 
diff --git a/src/newgrf_profiling.cpp b/src/newgrf_profiling.cpp
index b2d9a0cf5e..4e0cfec0f9 100644
--- a/src/newgrf_profiling.cpp
+++ b/src/newgrf_profiling.cpp
@@ -113,7 +113,7 @@ uint32_t NewGRFProfiler::Finish()
 	} else {
 		fmt::print(*f, "Tick,Sprite,Feature,Item,CallbackID,Microseconds,Depth,Result\n");
 		for (const Call &c : this->calls) {
-			fmt::print(*f, "{},{},{:#X},{},{:#X},{},{},{}\n", c.tick, c.root_sprite, c.feat, c.item, (uint)c.cb, c.time, c.subs, c.result);
+			fmt::print(*f, "{},{},0x{:X},{},0x{:X},{},{},{}\n", c.tick, c.root_sprite, c.feat, c.item, (uint)c.cb, c.time, c.subs, c.result);
 			total_microseconds += c.time;
 		}
 	}
diff --git a/src/newgrf_text.cpp b/src/newgrf_text.cpp
index 30a07a5ed5..f866fc4760 100644
--- a/src/newgrf_text.cpp
+++ b/src/newgrf_text.cpp
@@ -28,7 +28,6 @@
 #include "debug.h"
 #include "core/alloc_type.hpp"
 #include "language.h"
-#include <sstream>
 
 #include "table/strings.h"
 #include "table/control_codes.h"
diff --git a/src/pathfinder/yapf/yapf_type.hpp b/src/pathfinder/yapf/yapf_type.hpp
index fe2666b264..a39304fcfd 100644
--- a/src/pathfinder/yapf/yapf_type.hpp
+++ b/src/pathfinder/yapf/yapf_type.hpp
@@ -10,9 +10,6 @@
 #ifndef YAPF_TYPE_HPP
 #define YAPF_TYPE_HPP
 
-#include <iomanip>
-#include <sstream>
-
 #include "../../core/enum_type.hpp"
 #include "../../misc/dbg_helpers.h"
 
@@ -75,10 +72,7 @@ inline std::string ValueStr(EndSegmentReasons flags)
 		"PATH_TOO_LONG", "FIRST_TWO_WAY_RED", "LOOK_AHEAD_END", "TARGET_REACHED"
 	};
 
-	std::stringstream ss;
-	ss << "0x" << std::setfill('0') << std::setw(4) << std::hex << flags.base(); // 0x%04X
-	ss << " (" << ComposeNameT(flags, end_segment_reason_names, "UNK") << ")";
-	return ss.str();
+	return fmt::format("0x{:04X} ({})", flags.base(), ComposeNameT(flags, end_segment_reason_names, "UNK"));
 }
 
 #endif /* YAPF_TYPE_HPP */
diff --git a/src/saveload/strings_sl.cpp b/src/saveload/strings_sl.cpp
index f40721e074..2be7fe0f4a 100644
--- a/src/saveload/strings_sl.cpp
+++ b/src/saveload/strings_sl.cpp
@@ -11,7 +11,6 @@
 #include "../string_func.h"
 #include "../strings_func.h"
 #include "saveload_internal.h"
-#include <sstream>
 
 #include "table/strings.h"
 
diff --git a/src/string.cpp b/src/string.cpp
index 966a3b6af7..b2e085536b 100644
--- a/src/string.cpp
+++ b/src/string.cpp
@@ -17,9 +17,6 @@
 
 #include "table/control_codes.h"
 
-#include <sstream>
-#include <iomanip>
-
 #ifdef _MSC_VER
 #	define strncasecmp strnicmp
 #endif
diff --git a/src/town_gui.cpp b/src/town_gui.cpp
index f0433bcc48..a5c4cc7560 100644
--- a/src/town_gui.cpp
+++ b/src/town_gui.cpp
@@ -50,8 +50,6 @@
 
 #include "table/strings.h"
 
-#include <sstream>
-
 #include "safeguards.h"
 
 TownKdtree _town_local_authority_kdtree{};
diff --git a/src/vehicle_cmd.cpp b/src/vehicle_cmd.cpp
index 6a3a889f22..89bae13ccd 100644
--- a/src/vehicle_cmd.cpp
+++ b/src/vehicle_cmd.cpp
@@ -37,8 +37,7 @@
 #include "roadveh_cmd.h"
 #include "train_cmd.h"
 #include "ship_cmd.h"
-#include <sstream>
-#include <iomanip>
+#include <charconv>
 
 #include "table/strings.h"
 
@@ -803,23 +802,19 @@ static void CloneVehicleName(const Vehicle *src, Vehicle *dst)
 		/* Found digits, parse them and start at the next number. */
 		buf = src->name.substr(0, number_position);
 
-		auto num_str = src->name.substr(number_position);
+		auto num_str = std::string_view(src->name).substr(number_position);
 		padding = (uint8_t)num_str.length();
 
-		std::istringstream iss(num_str);
-		iss >> num;
+		[[maybe_unused]] auto err = std::from_chars(num_str.data(), num_str.data() + num_str.size(), num, 10).ec;
+		assert(err == std::errc());
 		num++;
 	}
 
 	/* Check if this name is already taken. */
 	for (int max_iterations = 1000; max_iterations > 0; max_iterations--, num++) {
-		std::ostringstream oss;
-
-		/* Attach the number to the temporary name. */
-		oss << buf << std::setw(padding) << std::setfill('0') << std::internal << num;
+		std::string new_name = fmt::format("{}{:0{}}", buf, num, padding);
 
 		/* Check the name is unique. */
-		auto new_name = oss.str();
 		if (IsUniqueVehicleName(new_name)) {
 			dst->name = std::move(new_name);
 			break;