diff --git a/src/unity_internals.h b/src/unity_internals.h
index 640ebeb..253c5b9 100644
--- a/src/unity_internals.h
+++ b/src/unity_internals.h
@@ -454,11 +454,11 @@ void UnityAssertEqualDoubleArray(const _UD* expected,
 #define UNITY_TEST_ASSERT_EQUAL_HEX32(expected, actual, line, message)                           UnityAssertEqualNumber((_U_SINT)(_US32)(expected), (_U_SINT)(_US32)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX32)
 #define UNITY_TEST_ASSERT_BITS(mask, expected, actual, line, message)                            UnityAssertBits((_U_SINT)(mask), (_U_SINT)(expected), (_U_SINT)(actual), (message), (UNITY_LINE_TYPE)line)
 
-#define UNITY_TEST_ASSERT_INT_WITHIN(delta, expected, actual, line, message)                     UnityAssertNumbersWithin((_U_SINT)(delta), (_U_SINT)(expected), (_U_SINT)(actual), NULL, (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_INT)
-#define UNITY_TEST_ASSERT_UINT_WITHIN(delta, expected, actual, line, message)                    UnityAssertNumbersWithin((_U_SINT)(delta), (_U_SINT)(expected), (_U_SINT)(actual), NULL, (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_UINT)
-#define UNITY_TEST_ASSERT_HEX8_WITHIN(delta, expected, actual, line, message)                    UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU8 )(delta), (_U_SINT)(_U_UINT)(_UU8 )(expected), (_U_SINT)(_U_UINT)(_UU8 )(actual), NULL, (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX8)
-#define UNITY_TEST_ASSERT_HEX16_WITHIN(delta, expected, actual, line, message)                   UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU16)(delta), (_U_SINT)(_U_UINT)(_UU16)(expected), (_U_SINT)(_U_UINT)(_UU16)(actual), NULL, (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX16)
-#define UNITY_TEST_ASSERT_HEX32_WITHIN(delta, expected, actual, line, message)                   UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU32)(delta), (_U_SINT)(_U_UINT)(_UU32)(expected), (_U_SINT)(_U_UINT)(_UU32)(actual), NULL, (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX32)
+#define UNITY_TEST_ASSERT_INT_WITHIN(delta, expected, actual, line, message)                     UnityAssertNumbersWithin((_U_SINT)(delta), (_U_SINT)(expected), (_U_SINT)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_INT)
+#define UNITY_TEST_ASSERT_UINT_WITHIN(delta, expected, actual, line, message)                    UnityAssertNumbersWithin((_U_SINT)(delta), (_U_SINT)(expected), (_U_SINT)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_UINT)
+#define UNITY_TEST_ASSERT_HEX8_WITHIN(delta, expected, actual, line, message)                    UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU8 )(delta), (_U_SINT)(_U_UINT)(_UU8 )(expected), (_U_SINT)(_U_UINT)(_UU8 )(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX8)
+#define UNITY_TEST_ASSERT_HEX16_WITHIN(delta, expected, actual, line, message)                   UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU16)(delta), (_U_SINT)(_U_UINT)(_UU16)(expected), (_U_SINT)(_U_UINT)(_UU16)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX16)
+#define UNITY_TEST_ASSERT_HEX32_WITHIN(delta, expected, actual, line, message)                   UnityAssertNumbersWithin((_U_SINT)(_U_UINT)(_UU32)(delta), (_U_SINT)(_U_UINT)(_UU32)(expected), (_U_SINT)(_U_UINT)(_UU32)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_HEX32)
 
 #define UNITY_TEST_ASSERT_EQUAL_PTR(expected, actual, line, message)                             UnityAssertEqualNumber((_U_SINT)(_UP)(expected), (_U_SINT)(_UP)(actual), (message), (UNITY_LINE_TYPE)line, UNITY_DISPLAY_STYLE_POINTER)
 #define UNITY_TEST_ASSERT_EQUAL_STRING(expected, actual, line, message)                          UnityAssertEqualString((const char*)(expected), (const char*)(actual), (message), (UNITY_LINE_TYPE)line)
diff --git a/test/testunity.c b/test/testunity.c
index 8c42534..8f6d353 100644
--- a/test/testunity.c
+++ b/test/testunity.c
@@ -699,6 +699,18 @@ void testIntsWithinDelta(void)
     TEST_ASSERT_INT_WITHIN(5, -1, 1);
 }
 
+void testIntsWithinDeltaAndCustomMessage(void)
+{
+    TEST_ASSERT_INT_WITHIN_MESSAGE(1, 5000, 5001, "Custom Message.");
+    TEST_ASSERT_INT_WITHIN_MESSAGE(5, 5000, 4996, "Custom Message.");
+    TEST_ASSERT_INT_WITHIN_MESSAGE(5, 5000, 5005, "Custom Message.");
+    TEST_ASSERT_INT_WITHIN_MESSAGE(500, 50, -440, "Custom Message.");
+    
+    TEST_ASSERT_INT_WITHIN_MESSAGE(2, -1, -1, "Custom Message.");
+    TEST_ASSERT_INT_WITHIN_MESSAGE(5, 1, -1, "Custom Message.");
+    TEST_ASSERT_INT_WITHIN_MESSAGE(5, -1, 1, "Custom Message.");
+}
+
 void testIntsNotWithinDelta(void)
 {
     EXPECT_ABORT_BEGIN
@@ -706,6 +718,13 @@ void testIntsNotWithinDelta(void)
     VERIFY_FAILS_END
 }
 
+void testIntsNotWithinDeltaAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_INT_WITHIN_MESSAGE(5, 5000, 5006, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testUIntsWithinDelta(void)
 {
     TEST_ASSERT_UINT_WITHIN(1, 5000, 5001);
@@ -713,6 +732,13 @@ void testUIntsWithinDelta(void)
     TEST_ASSERT_UINT_WITHIN(5, 5000, 5005);
 }
 
+void testUIntsWithinDeltaAndCustomMessage(void)
+{
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(1, 5000, 5001, "Custom Message.");
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(5, 5000, 4996, "Custom Message.");
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(5, 5000, 5005, "Custom Message.");
+}
+
 void testUIntsNotWithinDelta(void)
 {
     EXPECT_ABORT_BEGIN
@@ -720,6 +746,13 @@ void testUIntsNotWithinDelta(void)
     VERIFY_FAILS_END
 }
 
+void testUIntsNotWithinDeltaAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(1, 2147483647u, 2147483649u, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassSmallFirst(void)
 {
     EXPECT_ABORT_BEGIN
@@ -727,6 +760,13 @@ void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassSmallFirst(void)
     VERIFY_FAILS_END
 }
 
+void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassSmallFirstAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(5, 1, -1, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassBigFirst(void)
 {
     EXPECT_ABORT_BEGIN
@@ -734,6 +774,13 @@ void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassBigFirst(void)
     VERIFY_FAILS_END
 }
 
+void testUIntsNotWithinDeltaEvenThoughASignedIntWouldPassBigFirstAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_UINT_WITHIN_MESSAGE(5, -1, 1, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testHEX32sWithinDelta(void)
 {
     TEST_ASSERT_HEX32_WITHIN(1, 5000, 5001);
@@ -741,6 +788,13 @@ void testHEX32sWithinDelta(void)
     TEST_ASSERT_HEX32_WITHIN(5, 5000, 5005);
 }
 
+void testHEX32sWithinDeltaAndCustomMessage(void)
+{
+    TEST_ASSERT_HEX32_WITHIN_MESSAGE(1, 5000, 5001, "Custom Message.");
+    TEST_ASSERT_HEX32_WITHIN_MESSAGE(5, 5000, 4996, "Custom Message.");
+    TEST_ASSERT_HEX32_WITHIN_MESSAGE(5, 5000, 5005, "Custom Message.");
+}
+
 void testHEX32sNotWithinDelta(void)
 {
     EXPECT_ABORT_BEGIN
@@ -748,6 +802,13 @@ void testHEX32sNotWithinDelta(void)
     VERIFY_FAILS_END
 }
 
+void testHEX32sNotWithinDeltaAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_HEX32_WITHIN_MESSAGE(1, 2147483647u, 2147483649u, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testHEX32sNotWithinDeltaEvenThoughASignedIntWouldPass(void)
 {
     EXPECT_ABORT_BEGIN
@@ -755,6 +816,13 @@ void testHEX32sNotWithinDeltaEvenThoughASignedIntWouldPass(void)
     VERIFY_FAILS_END
 }
 
+void testHEX32sNotWithinDeltaEvenThoughASignedIntWouldPassAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_HEX32_WITHIN_MESSAGE(5, 1, -1, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testHEX16sWithinDelta(void)
 {
     TEST_ASSERT_HEX16_WITHIN(1, 5000, 5001);
@@ -762,11 +830,23 @@ void testHEX16sWithinDelta(void)
     TEST_ASSERT_HEX16_WITHIN(5, 5000, 5005);
 }
 
+void testHEX16sWithinDeltaAndCustomMessage(void)
+{
+    TEST_ASSERT_HEX16_WITHIN_MESSAGE(1, 5000, 5001, "Custom Message.");
+    TEST_ASSERT_HEX16_WITHIN_MESSAGE(5, 5000, 4996, "Custom Message.");
+    TEST_ASSERT_HEX16_WITHIN_MESSAGE(5, 5000, 5005, "Custom Message.");
+}
+
 void testHEX16sWithinDeltaWhenThereAreDifferenceOutsideOf16Bits(void)
 {
     TEST_ASSERT_HEX16_WITHIN(5, 0x54321, 0x44321); 
 }
 
+void testHEX16sWithinDeltaWhenThereAreDifferenceOutsideOf16BitsAndCustomMessage(void)
+{
+    TEST_ASSERT_HEX16_WITHIN_MESSAGE(5, 0x54321, 0x44321, "Custom Message."); 
+}
+
 void testHEX16sNotWithinDelta(void)
 {
     EXPECT_ABORT_BEGIN
@@ -774,6 +854,13 @@ void testHEX16sNotWithinDelta(void)
     VERIFY_FAILS_END
 }
 
+void testHEX16sNotWithinDeltaAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_HEX16_WITHIN_MESSAGE(2, 65535, 0, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testHEX8sWithinDelta(void)
 {
     TEST_ASSERT_HEX8_WITHIN(1, 254, 255);
@@ -781,11 +868,23 @@ void testHEX8sWithinDelta(void)
     TEST_ASSERT_HEX8_WITHIN(5, 1, 4);
 }
 
+void testHEX8sWithinDeltaAndCustomMessage(void)
+{
+    TEST_ASSERT_HEX8_WITHIN_MESSAGE(1, 254, 255, "Custom Message.");
+    TEST_ASSERT_HEX8_WITHIN_MESSAGE(5, 251, 255, "Custom Message.");
+    TEST_ASSERT_HEX8_WITHIN_MESSAGE(5, 1, 4, "Custom Message.");
+}
+
 void testHEX8sWithinDeltaWhenThereAreDifferenceOutsideOf8Bits(void)
 {
     TEST_ASSERT_HEX8_WITHIN(5, 0x123, 0xF23); 
 }
 
+void testHEX8sWithinDeltaWhenThereAreDifferenceOutsideOf8BitsAndCustomMessage(void)
+{
+    TEST_ASSERT_HEX8_WITHIN_MESSAGE(5, 0x123, 0xF23, "Custom Message."); 
+}
+
 void testHEX8sNotWithinDelta(void)
 {
     EXPECT_ABORT_BEGIN
@@ -793,6 +892,13 @@ void testHEX8sNotWithinDelta(void)
     VERIFY_FAILS_END
 }
 
+void testHEX8sNotWithinDeltaAndCustomMessage(void)
+{
+    EXPECT_ABORT_BEGIN
+    TEST_ASSERT_HEX8_WITHIN_MESSAGE(2, 255, 0, "Custom Message.");
+    VERIFY_FAILS_END
+}
+
 void testEqualStrings(void)
 {
     const char *testString = "foo";