diff --git a/Marlin/src/Marlin.cpp b/Marlin/src/Marlin.cpp
index 493ca94153..65cafbcc30 100644
--- a/Marlin/src/Marlin.cpp
+++ b/Marlin/src/Marlin.cpp
@@ -360,33 +360,8 @@ void suicide() {
  ***************** GCode Handlers *****************
  **************************************************/
 
-#if ENABLED(SDSUPPORT)
-  #include "gcode/sdcard/M20.h"           // M20  - List SD card. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M21.h"           // M21  - Init SD card. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M22.h"           // M22  - Release SD card. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M23.h"           // M23  - Select SD file: "M23 /path/file.gco". (Requires SDSUPPORT)
-  #include "gcode/sdcard/M24.h"           // M24  - Start/resume SD print. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M25.h"           // M25  - Pause SD print. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M26.h"           // M26  - Set SD position in bytes: "M26 S12345". (Requires SDSUPPORT)
-  #include "gcode/sdcard/M27.h"           // M27  - Report SD print status. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M28.h"           // M28  - Start SD write: "M28 /path/file.gco". (Requires SDSUPPORT)
-  #include "gcode/sdcard/M29.h"           // M29  - Stop SD write. (Requires SDSUPPORT)
-  #include "gcode/sdcard/M30.h"           // M30  - Delete file from SD: "M30 /path/file.gco"
-#endif
-
 #include "gcode/stats/M31.h"              // M31: Get the time since the start of SD Print (or last M109)
 
-#if ENABLED(SDSUPPORT)
-  #include "gcode/sdcard/M32.h"
-  #if ENABLED(LONG_FILENAME_HOST_SUPPORT)
-    #include "gcode/sdcard/M33.h"
-  #endif
-  #if ENABLED(SDCARD_SORT_ALPHA) && ENABLED(SDSORT_GCODE)
-    #include "gcode/sdcard/M34.h"
-  #endif
-  #include "gcode/sdcard/M928.h"
-#endif
-
 /**
  * Sensitive pin test for M42, M226
  */
diff --git a/Marlin/src/gcode/gcode.cpp b/Marlin/src/gcode/gcode.cpp
index e41444f0f2..799a5df58a 100644
--- a/Marlin/src/gcode/gcode.cpp
+++ b/Marlin/src/gcode/gcode.cpp
@@ -117,20 +117,7 @@ void GcodeSuite::dwell(millis_t time) {
 // Placeholders for non-migrated codes
 //
 extern void gcode_M18_M84();
-extern void gcode_M20();
-extern void gcode_M21();
-extern void gcode_M22();
-extern void gcode_M23();
-extern void gcode_M25();
-extern void gcode_M26();
-extern void gcode_M27();
-extern void gcode_M28();
-extern void gcode_M29();
-extern void gcode_M30();
 extern void gcode_M31();
-extern void gcode_M32();
-extern void gcode_M33();
-extern void gcode_M34();
 extern void gcode_M42();
 extern void gcode_M43();
 extern void gcode_M48();
@@ -160,7 +147,6 @@ extern void gcode_M118();
 extern void gcode_M119();
 extern void gcode_M120();
 extern void gcode_M121();
-extern void gcode_M125();
 extern void gcode_M126();
 extern void gcode_M127();
 extern void gcode_M128();
@@ -225,7 +211,6 @@ extern void gcode_M907();
 extern void gcode_M908();
 extern void gcode_M909();
 extern void gcode_M910();
-extern void gcode_M928();
 extern void gcode_M999();
 extern void gcode_T(uint8_t tmp_extruder);
 
@@ -423,43 +408,28 @@ void GcodeSuite::process_next_command() {
         break;
 
       #if ENABLED(SDSUPPORT)
-        case 20: // M20: list SD card
-          gcode_M20(); break;
-        case 21: // M21: init SD card
-          gcode_M21(); break;
-        case 22: // M22: release SD card
-          gcode_M22(); break;
-        case 23: // M23: Select file
-          gcode_M23(); break;
-        case 24: // M24: Start SD print
-          M24(); break;
-        case 25: // M25: Pause SD print
-          gcode_M25(); break;
-        case 26: // M26: Set SD index
-          gcode_M26(); break;
-        case 27: // M27: Get SD status
-          gcode_M27(); break;
-        case 28: // M28: Start SD write
-          gcode_M28(); break;
-        case 29: // M29: Stop SD write
-          gcode_M29(); break;
-        case 30: // M30 <filename> Delete File
-          gcode_M30(); break;
-        case 32: // M32: Select file and start SD print
-          gcode_M32(); break;
+        case 20: M20(); break;    // M20: list SD card
+        case 21: M21(); break;    // M21: init SD card
+        case 22: M22(); break;    // M22: release SD card
+        case 23: M23(); break;    // M23: Select file
+        case 24: M24(); break;    // M24: Start SD print
+        case 25: M25(); break;    // M25: Pause SD print
+        case 26: M26(); break;    // M26: Set SD index
+        case 27: M27(); break;    // M27: Get SD status
+        case 28: M28(); break;    // M28: Start SD write
+        case 29: M29(); break;    // M29: Stop SD write
+        case 30: M30(); break;    // M30 <filename> Delete File
+        case 32: M32(); break;    // M32: Select file and start SD print
 
         #if ENABLED(LONG_FILENAME_HOST_SUPPORT)
-          case 33: // M33: Get the long full path to a file or folder
-            gcode_M33(); break;
+          case 33: M33(); break;  // M33: Get the long full path to a file or folder
         #endif
 
         #if ENABLED(SDCARD_SORT_ALPHA) && ENABLED(SDSORT_GCODE)
-          case 34: // M34: Set SD card sorting options
-            gcode_M34(); break;
-        #endif // SDCARD_SORT_ALPHA && SDSORT_GCODE
+          case 34: M34(); break;  // M34: Set SD card sorting options
+        #endif
 
-        case 928: // M928: Start SD write
-          gcode_M928(); break;
+        case 928: M928(); break;  // M928: Start SD write
       #endif // SDSUPPORT
 
       case 31: // M31: Report time since the start of SD print or last M109
diff --git a/Marlin/src/gcode/sdcard/M20.h b/Marlin/src/gcode/sdcard/M20.cpp
similarity index 86%
rename from Marlin/src/gcode/sdcard/M20.h
rename to Marlin/src/gcode/sdcard/M20.cpp
index 89b2d6d448..a5916f5292 100644
--- a/Marlin/src/gcode/sdcard/M20.h
+++ b/Marlin/src/gcode/sdcard/M20.cpp
@@ -20,11 +20,20 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M20: List SD card to serial output
  */
-void gcode_M20() {
+void GcodeSuite::M20() {
   SERIAL_PROTOCOLLNPGM(MSG_BEGIN_FILE_LIST);
   card.ls();
   SERIAL_PROTOCOLLNPGM(MSG_END_FILE_LIST);
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M21.h b/Marlin/src/gcode/sdcard/M21.cpp
similarity index 83%
rename from Marlin/src/gcode/sdcard/M21.h
rename to Marlin/src/gcode/sdcard/M21.cpp
index 3812bca034..90bf3372a0 100644
--- a/Marlin/src/gcode/sdcard/M21.h
+++ b/Marlin/src/gcode/sdcard/M21.cpp
@@ -20,7 +20,16 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M21: Init SD Card
  */
-void gcode_M21() { card.initsd(); }
+void GcodeSuite::M21() { card.initsd(); }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M22.h b/Marlin/src/gcode/sdcard/M22.cpp
similarity index 83%
rename from Marlin/src/gcode/sdcard/M22.h
rename to Marlin/src/gcode/sdcard/M22.cpp
index 3a8848829b..afb665ae64 100644
--- a/Marlin/src/gcode/sdcard/M22.h
+++ b/Marlin/src/gcode/sdcard/M22.cpp
@@ -20,7 +20,16 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M22: Release SD Card
  */
-void gcode_M22() { card.release(); }
+void GcodeSuite::M22() { card.release(); }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M23.h b/Marlin/src/gcode/sdcard/M23.cpp
similarity index 86%
rename from Marlin/src/gcode/sdcard/M23.h
rename to Marlin/src/gcode/sdcard/M23.cpp
index 46059e2d4f..41211e988a 100644
--- a/Marlin/src/gcode/sdcard/M23.h
+++ b/Marlin/src/gcode/sdcard/M23.cpp
@@ -20,11 +20,20 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M23: Open a file
  */
-void gcode_M23() {
+void GcodeSuite::M23() {
   // Simplify3D includes the size, so zero out all spaces (#7227)
   for (char *fn = parser.string_arg; *fn; ++fn) if (*fn == ' ') *fn = '\0';
   card.openFile(parser.string_arg, true);
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M25.h b/Marlin/src/gcode/sdcard/M25.cpp
similarity index 80%
rename from Marlin/src/gcode/sdcard/M25.h
rename to Marlin/src/gcode/sdcard/M25.cpp
index 7f466ad92f..8de3364215 100644
--- a/Marlin/src/gcode/sdcard/M25.h
+++ b/Marlin/src/gcode/sdcard/M25.cpp
@@ -20,10 +20,22 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+#include "../../module/printcounter.h"
+
+#if ENABLED(PARK_HEAD_ON_PAUSE)
+  #include "../queue.h"
+#endif
+
 /**
  * M25: Pause SD Print
  */
-void gcode_M25() {
+void GcodeSuite::M25() {
   card.pauseSDPrint();
   print_job_timer.pause();
 
@@ -31,3 +43,5 @@ void gcode_M25() {
     enqueue_and_echo_commands_P(PSTR("M125")); // Must be enqueued with pauseSDPrint set to be last in the buffer
   #endif
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M26.h b/Marlin/src/gcode/sdcard/M26.cpp
similarity index 85%
rename from Marlin/src/gcode/sdcard/M26.h
rename to Marlin/src/gcode/sdcard/M26.cpp
index a3eaf6121b..5efbeb393c 100644
--- a/Marlin/src/gcode/sdcard/M26.h
+++ b/Marlin/src/gcode/sdcard/M26.cpp
@@ -20,10 +20,19 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M26: Set SD Card file index
  */
-void gcode_M26() {
+void GcodeSuite::M26() {
   if (card.cardOK && parser.seenval('S'))
     card.setIndex(parser.value_long());
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M27.h b/Marlin/src/gcode/sdcard/M27.cpp
similarity index 83%
rename from Marlin/src/gcode/sdcard/M27.h
rename to Marlin/src/gcode/sdcard/M27.cpp
index 6825e8466b..439b976000 100644
--- a/Marlin/src/gcode/sdcard/M27.h
+++ b/Marlin/src/gcode/sdcard/M27.cpp
@@ -20,7 +20,16 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M27: Get SD Card status
  */
-void gcode_M27() { card.getStatus(); }
+void GcodeSuite::M27() { card.getStatus(); }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M28.h b/Marlin/src/gcode/sdcard/M28.cpp
similarity index 81%
rename from Marlin/src/gcode/sdcard/M28.h
rename to Marlin/src/gcode/sdcard/M28.cpp
index 5e8689f438..82200e83ab 100644
--- a/Marlin/src/gcode/sdcard/M28.h
+++ b/Marlin/src/gcode/sdcard/M28.cpp
@@ -20,7 +20,16 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M28: Start SD Write
  */
-void gcode_M28() { card.openFile(parser.string_arg, false); }
+void GcodeSuite::M28() { card.openFile(parser.string_arg, false); }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M29.h b/Marlin/src/gcode/sdcard/M29.cpp
similarity index 85%
rename from Marlin/src/gcode/sdcard/M29.h
rename to Marlin/src/gcode/sdcard/M29.cpp
index 341640981c..c5e2081cd3 100644
--- a/Marlin/src/gcode/sdcard/M29.h
+++ b/Marlin/src/gcode/sdcard/M29.cpp
@@ -20,10 +20,19 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M29: Stop SD Write
  * Processed in write to file routine above
  */
-void gcode_M29() {
+void GcodeSuite::M29() {
   // card.saving = false;
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M30.h b/Marlin/src/gcode/sdcard/M30.cpp
similarity index 85%
rename from Marlin/src/gcode/sdcard/M30.h
rename to Marlin/src/gcode/sdcard/M30.cpp
index 5d584a39b4..94335fe0f5 100644
--- a/Marlin/src/gcode/sdcard/M30.h
+++ b/Marlin/src/gcode/sdcard/M30.cpp
@@ -20,12 +20,21 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M30 <filename>: Delete SD Card file
  */
-void gcode_M30() {
+void GcodeSuite::M30() {
   if (card.cardOK) {
     card.closefile();
     card.removeFile(parser.string_arg);
   }
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M32.h b/Marlin/src/gcode/sdcard/M32.cpp
similarity index 84%
rename from Marlin/src/gcode/sdcard/M32.h
rename to Marlin/src/gcode/sdcard/M32.cpp
index 5938d8c5d7..de864f9cb3 100644
--- a/Marlin/src/gcode/sdcard/M32.h
+++ b/Marlin/src/gcode/sdcard/M32.cpp
@@ -20,10 +20,19 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+#include "../../module/stepper.h"
+#include "../../module/printcounter.h"
+
 /**
  * M32: Select file and start SD Print
  */
-void gcode_M32() {
+void GcodeSuite::M32() {
   if (IS_SD_PRINTING)
     stepper.synchronize();
 
@@ -42,3 +51,5 @@ void gcode_M32() {
     if (!call_procedure) print_job_timer.start();
   }
 }
+
+#endif // SDSUPPORT
diff --git a/Marlin/src/gcode/sdcard/M33.h b/Marlin/src/gcode/sdcard/M33.cpp
similarity index 83%
rename from Marlin/src/gcode/sdcard/M33.h
rename to Marlin/src/gcode/sdcard/M33.cpp
index 2380c9f532..69933df999 100644
--- a/Marlin/src/gcode/sdcard/M33.h
+++ b/Marlin/src/gcode/sdcard/M33.cpp
@@ -20,6 +20,13 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT) && ENABLED(LONG_FILENAME_HOST_SUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M33: Get the long full path of a file or folder
  *
@@ -32,6 +39,8 @@
  * Output:
  *   /Miscellaneous/Armchair/Armchair.gcode
  */
-void gcode_M33() {
+void GcodeSuite::M33() {
   card.printLongPath(parser.string_arg);
 }
+
+#endif // SDSUPPORT && LONG_FILENAME_HOST_SUPPORT
diff --git a/Marlin/src/gcode/sdcard/M34.h b/Marlin/src/gcode/sdcard/M34.cpp
similarity index 82%
rename from Marlin/src/gcode/sdcard/M34.h
rename to Marlin/src/gcode/sdcard/M34.cpp
index 189eaa2da9..911539d408 100644
--- a/Marlin/src/gcode/sdcard/M34.h
+++ b/Marlin/src/gcode/sdcard/M34.cpp
@@ -20,10 +20,17 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT) && ENABLED(SDCARD_SORT_ALPHA) && ENABLED(SDSORT_GCODE)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M34: Set SD Card Sorting Options
  */
-void gcode_M34() {
+void GcodeSuite::M34() {
   if (parser.seen('S')) card.setSortOn(parser.value_bool());
   if (parser.seenval('F')) {
     const int v = parser.value_long();
@@ -31,3 +38,5 @@ void gcode_M34() {
   }
   //if (parser.seen('R')) card.setSortReverse(parser.value_bool());
 }
+
+#endif // SDSUPPORT && SDCARD_SORT_ALPHA && SDSORT_GCODE
diff --git a/Marlin/src/gcode/sdcard/M928.h b/Marlin/src/gcode/sdcard/M928.cpp
similarity index 85%
rename from Marlin/src/gcode/sdcard/M928.h
rename to Marlin/src/gcode/sdcard/M928.cpp
index 41c83fe9f1..069448f0b9 100644
--- a/Marlin/src/gcode/sdcard/M928.h
+++ b/Marlin/src/gcode/sdcard/M928.cpp
@@ -20,9 +20,18 @@
  *
  */
 
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(SDSUPPORT)
+
+#include "../gcode.h"
+#include "../../sd/cardreader.h"
+
 /**
  * M928: Start SD Write
  */
-void gcode_M928() {
+void GcodeSuite::M928() {
   card.openLogFile(parser.string_arg);
 }
+
+#endif // SDSUPPORT