diff --git a/src/include/espeak-ng/espeak_ng.h b/src/include/espeak-ng/espeak_ng.h
index 3f8d7aae..f8ddc58e 100644
--- a/src/include/espeak-ng/espeak_ng.h
+++ b/src/include/espeak-ng/espeak_ng.h
@@ -188,6 +188,7 @@ espeak_ng_CompilePhonemeDataPath(long rate,
 typedef enum
 {
 	ESPEAKNG_ENCODING_UNKNOWN,
+	ESPEAKNG_ENCODING_US_ASCII,
 } espeak_ng_ENCODING;
 
 ESPEAK_NG_API espeak_ng_ENCODING
diff --git a/src/libespeak-ng/encoding.c b/src/libespeak-ng/encoding.c
index 550c49a2..44b246b8 100644
--- a/src/libespeak-ng/encoding.c
+++ b/src/libespeak-ng/encoding.c
@@ -21,8 +21,19 @@
 
 #include "speech.h"
 
+// http://www.iana.org/assignments/character-sets/character-sets.xhtml
 MNEM_TAB mnem_encoding[] = {
-	{ NULL,              ESPEAKNG_ENCODING_UNKNOWN }
+	{ "ANSI_X3.4-1968",   ESPEAKNG_ENCODING_US_ASCII },
+	{ "ANSI_X3.4-1986",   ESPEAKNG_ENCODING_US_ASCII },
+	{ "IBM367",           ESPEAKNG_ENCODING_US_ASCII },
+	{ "ISO_646.irv:1991", ESPEAKNG_ENCODING_US_ASCII },
+	{ "ISO646-US",        ESPEAKNG_ENCODING_US_ASCII },
+	{ "US-ASCII",         ESPEAKNG_ENCODING_US_ASCII },
+	{ "cp367",            ESPEAKNG_ENCODING_US_ASCII },
+	{ "csASCII",          ESPEAKNG_ENCODING_US_ASCII },
+	{ "iso-ir-6",         ESPEAKNG_ENCODING_US_ASCII },
+	{ "us",               ESPEAKNG_ENCODING_US_ASCII },
+	{ NULL,               ESPEAKNG_ENCODING_UNKNOWN }
 };
 
 #pragma GCC visibility push(default)
diff --git a/tests/encoding.c b/tests/encoding.c
index 1877cbeb..e01f9ae7 100644
--- a/tests/encoding.c
+++ b/tests/encoding.c
@@ -31,12 +31,31 @@ test_unknown_encoding()
 
 	assert(espeak_ng_EncodingFromName("") == ESPEAKNG_ENCODING_UNKNOWN);
 	assert(espeak_ng_EncodingFromName("abcxyz") == ESPEAKNG_ENCODING_UNKNOWN);
+	assert(espeak_ng_EncodingFromName("US") == ESPEAKNG_ENCODING_UNKNOWN); // wrong case
+}
+
+void
+test_us_ascii_encoding()
+{
+	printf("testing US-ASCII encoding\n");
+
+	assert(espeak_ng_EncodingFromName("US-ASCII") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("iso-ir-6") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("ANSI_X3.4-1968") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("ANSI_X3.4-1986") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("ISO_646.irv:1991") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("ISO646-US") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("us") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("IBM367") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("cp367") == ESPEAKNG_ENCODING_US_ASCII);
+	assert(espeak_ng_EncodingFromName("csASCII") == ESPEAKNG_ENCODING_US_ASCII);
 }
 
 int
 main(int argc, char **argv)
 {
 	test_unknown_encoding();
+	test_us_ascii_encoding();
 	printf("done\n");
 
 	return EXIT_SUCCESS;