diff --git a/CHANGELOG.md b/CHANGELOG.md
index e3fd2b4ed..b977f1c98 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to this project will be documented in this file.
 
 ## [14.3.0.3]
 ### Added
+- I2C over Serial, preliminary stub
 
 ### Breaking Changed
 
diff --git a/tasmota/include/tasmota_template.h b/tasmota/include/tasmota_template.h
index 5c694d28e..3788d9a8b 100644
--- a/tasmota/include/tasmota_template.h
+++ b/tasmota/include/tasmota_template.h
@@ -226,6 +226,7 @@ enum UserSelectablePins {
   GPIO_BL0906_RX,                       // BL0906 Serial interface
   GPIO_DALI_RX_INV, GPIO_DALI_TX_INV,   // DALI
   GPIO_LD2410S_TX, GPIO_LD2410S_RX,     // HLK-LD2410S
+  GPIO_I2C_SER_TX, GPIO_I2C_SER_RX,     // I2C via Serial using SC18IM704 protocol (xdrv74)
   GPIO_SENSOR_END };
 
 // Error as warning to rethink GPIO usage with max 2045
@@ -499,6 +500,7 @@ const char kSensorNames[] PROGMEM =
   D_SENSOR_BL0906_RX "|"
   D_SENSOR_DALI_RX "_i|" D_SENSOR_DALI_TX "_i|"
   D_SENSOR_LD2410S_TX "|" D_SENSOR_LD2410S_RX "|"
+  D_SENSOR_I2C_SER_TX "|" D_SENSOR_I2C_SER_RX "|"
   ;
 
 const char kSensorNamesFixed[] PROGMEM =
@@ -602,6 +604,10 @@ const uint16_t kGpioNiceList[] PROGMEM = {
 #ifdef USE_PCF8574
   AGPIO(GPIO_PCF8574_INT),              // PCF8574 Interrupt
 #endif  // USE_PCF8574
+#ifdef USE_I2C_SERIAL
+  AGPIO(GPIO_I2C_SER_TX) + MAX_I2C,     // I2C via Serial TX
+  AGPIO(GPIO_I2C_SER_RX) + MAX_I2C,     // I2C via Serial RX
+#endif // USE_I2C_SERIAL
 #endif
 
 #if defined(USE_I2S_AUDIO) || defined (USE_I2S)
diff --git a/tasmota/language/af_AF.h b/tasmota/language/af_AF.h
index 49fcb7f03..cad4d22a4 100644
--- a/tasmota/language/af_AF.h
+++ b/tasmota/language/af_AF.h
@@ -698,6 +698,8 @@
 #define D_SENSOR_DS18X20       "DS18x20"
 #define D_SENSOR_I2C_SCL       "I2C SCL"
 #define D_SENSOR_I2C_SDA       "I2C SDA"
+#define D_SENSOR_I2C_SER_TX    "I2C Ser TX"
+#define D_SENSOR_I2C_SER_RX    "I2C Ser RX"
 #define D_SENSOR_I2S_MCLK      "I2S MCLK"
 #define D_SENSOR_I2S_BCLK      "I2S BCLK"
 #define D_SENSOR_I2S_WS_IN     "I2S BCLK IN"
diff --git a/tasmota/language/bg_BG.h b/tasmota/language/bg_BG.h
index 00b556988..e633d6cbb 100644
--- a/tasmota/language/bg_BG.h
+++ b/tasmota/language/bg_BG.h
@@ -698,6 +698,8 @@
 #define D_SENSOR_DS18X20       "DS18x20"
 #define D_SENSOR_I2C_SCL       "I2C SCL"
 #define D_SENSOR_I2C_SDA       "I2C SDA"
+#define D_SENSOR_I2C_SER_TX    "I2C Ser TX"
+#define D_SENSOR_I2C_SER_RX    "I2C Ser RX"
 #define D_SENSOR_I2S_MCLK      "I2S MCLK"
 #define D_SENSOR_I2S_BCLK      "I2S BCLK"
 #define D_SENSOR_I2S_WS_IN     "I2S BCLK IN"
diff --git a/tasmota/language/ca_AD.h b/tasmota/language/ca_AD.h
index c8234cd9f..fe0ffe9f5 100644
--- a/tasmota/language/ca_AD.h
+++ b/tasmota/language/ca_AD.h
@@ -698,6 +698,8 @@
 #define D_SENSOR_DS18X20       "DS18x20"
 #define D_SENSOR_I2C_SCL       "I2C SCL"
 #define D_SENSOR_I2C_SDA       "I2C SDA"
+#define D_SENSOR_I2C_SER_TX    "I2C Ser TX"
+#define D_SENSOR_I2C_SER_RX    "I2C Ser RX"
 #define D_SENSOR_I2S_MCLK      "I2S MCLK"
 #define D_SENSOR_I2S_BCLK      "I2S BCLK"
 #define D_SENSOR_I2S_WS_IN     "I2S BCLK IN"
diff --git a/tasmota/language/cs_CZ.h b/tasmota/language/cs_CZ.h
index 3e58a9142..6685140f2 100644
--- a/tasmota/language/cs_CZ.h
+++ b/tasmota/language/cs_CZ.h
@@ -698,6 +698,8 @@
 #define D_SENSOR_DS18X20       "DS18x20"
 #define D_SENSOR_I2C_SCL       "I2C SCL"
 #define D_SENSOR_I2C_SDA       "I2C SDA"
+#define D_SENSOR_I2C_SER_TX    "I2C Ser TX"
+#define D_SENSOR_I2C_SER_RX    "I2C Ser RX"
 #define D_SENSOR_I2S_MCLK      "I2S MCLK"
 #define D_SENSOR_I2S_BCLK      "I2S BCLK"
 #defin