diff --git a/phosphor-regulators/src/config_file_parser.cpp b/phosphor-regulators/src/config_file_parser.cpp
index cdf758e..791f3f7 100644
--- a/phosphor-regulators/src/config_file_parser.cpp
+++ b/phosphor-regulators/src/config_file_parser.cpp
@@ -108,9 +108,8 @@
     }
     else if (element.contains("i2c_write_byte"))
     {
-        // TODO: Not implemented yet
-        // action = parseI2CWriteByte(element["i2c_write_byte"]);
-        // ++propertyCount;
+        action = parseI2CWriteByte(element["i2c_write_byte"]);
+        ++propertyCount;
     }
     else if (element.contains("i2c_write_bytes"))
     {
@@ -220,6 +219,36 @@
     return std::make_unique<I2CWriteBitAction>(reg, position, value);
 }
 
+std::unique_ptr<I2CWriteByteAction> parseI2CWriteByte(const json& element)
+{
+    verifyIsObject(element);
+    unsigned int propertyCount{0};
+
+    // Required register property
+    const json& regElement = getRequiredProperty(element, "register");
+    uint8_t reg = parseStringToUint8(regElement);
+    ++propertyCount;
+
+    // Required value property
+    const json& valueElement = getRequiredProperty(element, "value");
+    uint8_t value = parseStringToUint8(valueElement);
+    ++propertyCount;
+
+    // Optional mask property
+    uint8_t mask = 0xff;
+    auto maskIt = element.find("mask");
+    if (maskIt != element.end())
+    {
+        mask = parseStringToUint8(*maskIt);
+        ++propertyCount;
+    }
+
+    // Verify no invalid properties exist
+    verifyPropertyCount(element, propertyCount);
+
+    return std::make_unique<I2CWriteByteAction>(reg, value, mask);
+}
+
 std::unique_ptr<PMBusWriteVoutCommandAction>
     parsePMBusWriteVoutCommand(const json& element)
 {
diff --git a/phosphor-regulators/src/config_file_parser.hpp b/phosphor-regulators/src/config_file_parser.hpp
index f96e6b4..abfa4f5 100644
--- a/phosphor-regulators/src/config_file_parser.hpp
+++ b/phosphor-regulators/src/config_file_parser.hpp
@@ -18,6 +18,7 @@
 #include "action.hpp"
 #include "chassis.hpp"
 #include "i2c_write_bit_action.hpp"
+#include "i2c_write_byte_action.hpp"
 #include "pmbus_write_vout_command_action.hpp"
 #include "rule.hpp"
 
@@ -215,6 +216,19 @@
     parseI2CWriteBit(const nlohmann::json& element);
 
 /**
+ * Parses a JSON element containing an i2c_write_byte action.
+ *
+ * Returns the corresponding C++ I2CWriteByteAction object.
+ *
+ * Throws an exception if parsing fails.
+ *
+ * @param element JSON element
+ * @return I2CWriteByteAction object
+ */
+std::unique_ptr<I2CWriteByteAction>
+    parseI2CWriteByte(const nlohmann::json& element);
+
+/**
  * Parses a JSON element containing an 8-bit signed integer.
  *
  * Returns the corresponding C++ int8_t value.
diff --git a/phosphor-regulators/test/config_file_parser_tests.cpp b/phosphor-regulators/test/config_file_parser_tests.cpp
index c26f472..7d36653 100644
--- a/phosphor-regulators/test/config_file_parser_tests.cpp
+++ b/phosphor-regulators/test/config_file_parser_tests.cpp
@@ -19,6 +19,7 @@
 #include "config_file_parser_error.hpp"
 #include "i2c_interface.hpp"
 #include "i2c_write_bit_action.hpp"
+#include "i2c_write_byte_action.hpp"
 #include "pmbus_utils.hpp"
 #include "pmbus_write_vout_command_action.hpp"
 #include "rule.hpp"
@@ -263,7 +264,18 @@
     }
 
     // Test where works: i2c_write_byte action type specified
-    // TODO: Not implemented yet
+    {
+        const json element = R"(
+            {
+              "i2c_write_byte": {
+                "register": "0x0A",
+                "value": "0xCC"
+              }
+            }
+        )"_json;
+        std::unique_ptr<Action> action = parseAction(element);
+        EXPECT_NE(action.get(), nullptr);
+    }
 
     // Test where works: i2c_write_bytes action type specified
     // TODO: Not implemented yet
@@ -551,59 +563,6 @@
     }
 }
 
-TEST(ConfigFileParserTests, ParseInt8)
-{
-    // Test where works: INT8_MIN
-    {
-        const json element = R"( -128 )"_json;
-        int8_t value = parseInt8(element);
-        EXPECT_EQ(value, -128);
-    }
-
-    // Test where works: INT8_MAX
-    {
-        const json element = R"( 127 )"_json;
-        int8_t value = parseInt8(element);
-        EXPECT_EQ(value, 127);
-    }
-
-    // Test where fails: Element is not an integer
-    try
-    {
-        const json element = R"( 1.03 )"_json;
-        parseInt8(element);
-        ADD_FAILURE() << "Should not have reached this line.";
-    }
-    catch (const std::invalid_argument& e)
-    {
-        EXPECT_STREQ(e.what(), "Element is not an integer");
-    }
-
-    // Test where fails: Value < INT8_MIN
-    try
-    {
-        const json element = R"( -129 )"_json;
-        parseInt8(element);
-        ADD_FAILURE() << "Should not have reached this line.";
-    }
-    catch (const std::invalid_argument& e)
-    {
-        EXPECT_STREQ(e.what(), "Element is not an 8-bit signed integer");
-    }
-
-    // Test where fails: Value > INT8_MAX
-    try
-    {
-        const json element = R"( 128 )"_json;
-        parseInt8(element);
-        ADD_FAILURE() << "Should not have reached this line.";
-    }
-    catch (const std::invalid_argument& e)
-    {
-        EXPECT_STREQ(e.what(), "Element is not an 8-bit signed integer");
-    }
-}
-
 TEST(ConfigFileParserTests, ParseI2CWriteBit)
 {
     // Test where works
@@ -758,6 +717,210 @@
     }
 }
 
+TEST(ConfigFileParserTests, ParseI2CWriteByte)
+{
+    // Test where works: Only required properties specified
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "value": "0xCC"
+            }
+        )"_json;
+        std::unique_ptr<I2CWriteByteAction> action = parseI2CWriteByte(element);
+        EXPECT_EQ(action->getRegister(), 0x0A);
+        EXPECT_EQ(action->getValue(), 0xCC);
+        EXPECT_EQ(action->getMask(), 0xFF);
+    }
+
+    // Test where works: All properties specified
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "value": "0xCC",
+              "mask": "0xF7"
+            }
+        )"_json;
+        std::unique_ptr<I2CWriteByteAction> action = parseI2CWriteByte(element);
+        EXPECT_EQ(action->getRegister(), 0x0A);
+        EXPECT_EQ(action->getValue(), 0xCC);
+        EXPECT_EQ(action->getMask(), 0xF7);
+    }
+
+    // Test where fails: Element is not an object
+    try
+    {
+        const json element = R"( [ "0xFF", "0x01" ] )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an object");
+    }
+
+    // Test where fails: Invalid property specified
+    try
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "value": "0xCC",
+              "mask": "0xF7",
+              "foo": 1
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element contains an invalid property");
+    }
+
+    // Test where fails: register value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "register": "0x0Z",
+              "value": "0xCC",
+              "mask": "0xF7"
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not hexadecimal string");
+    }
+
+    // Test where fails: value value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "value": "0xCCC",
+              "mask": "0xF7"
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not hexadecimal string");
+    }
+
+    // Test where fails: mask value is invalid
+    try
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "value": "0xCC",
+              "mask": "F7"
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not hexadecimal string");
+    }
+
+    // Test where fails: Required register property not specified
+    try
+    {
+        const json element = R"(
+            {
+              "value": "0xCC",
+              "mask": "0xF7"
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Required property missing: register");
+    }
+
+    // Test where fails: Required value property not specified
+    try
+    {
+        const json element = R"(
+            {
+              "register": "0x0A",
+              "mask": "0xF7"
+            }
+        )"_json;
+        parseI2CWriteByte(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Required property missing: value");
+    }
+}
+
+TEST(ConfigFileParserTests, ParseInt8)
+{
+    // Test where works: INT8_MIN
+    {
+        const json element = R"( -128 )"_json;
+        int8_t value = parseInt8(element);
+        EXPECT_EQ(value, -128);
+    }
+
+    // Test where works: INT8_MAX
+    {
+        const json element = R"( 127 )"_json;
+        int8_t value = parseInt8(element);
+        EXPECT_EQ(value, 127);
+    }
+
+    // Test where fails: Element is not an integer
+    try
+    {
+        const json element = R"( 1.03 )"_json;
+        parseInt8(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an integer");
+    }
+
+    // Test where fails: Value < INT8_MIN
+    try
+    {
+        const json element = R"( -129 )"_json;
+        parseInt8(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an 8-bit signed integer");
+    }
+
+    // Test where fails: Value > INT8_MAX
+    try
+    {
+        const json element = R"( 128 )"_json;
+        parseInt8(element);
+        ADD_FAILURE() << "Should not have reached this line.";
+    }
+    catch (const std::invalid_argument& e)
+    {
+        EXPECT_STREQ(e.what(), "Element is not an 8-bit signed integer");
+    }
+}
+
 TEST(ConfigFileParserTests, ParsePMBusWriteVoutCommand)
 {
     // Test where works: Only required properties specified