diff --git a/pySim-prog.py b/pySim-prog.py
index 09a5d70f..a7081ff1 100755
--- a/pySim-prog.py
+++ b/pySim-prog.py
@@ -119,6 +119,9 @@ def parse_options():
 	parser.add_option("-i", "--imsi", dest="imsi",
 			help="International Mobile Subscriber Identity",
 		)
+	parser.add_option("--msisdn", dest="msisdn",
+			help="Mobile Subscriber Integrated Services Digital Number",
+		)
 	parser.add_option("-k", "--ki", dest="ki",
 			help="Ki (default is to randomize)",
 		)
@@ -165,7 +168,6 @@ def parse_options():
 	parser.add_option("--dry-run", dest="dry_run",
 			help="Perform a 'dry run', don't actually program the card",
 			default=False, action="store_true")
-
 	parser.add_option("--card_handler", dest="card_handler", metavar="FILE",
 			help="Use automatic card handling machine")
 
@@ -278,6 +280,17 @@ def gen_parameters(opts):
 		if len(opts.name) > 16:
 			raise ValueError('Service Provider Name must max 16 characters!');
 
+	if opts.msisdn is not None:
+		msisdn = opts.msisdn
+		if msisdn[0] == '+':
+			msisdn = msisdn[1:]
+		if not msisdn.isdigit():
+			raise ValueError('MSISDN must be digits only! '
+					 'Start with \'+\' for international numbers.')
+		if len(msisdn) > 10 * 2:
+			# TODO: Support MSISDN of length > 20 (10 Bytes)
+			raise ValueError('MSISDNs longer than 20 digits are not (yet) supported.')
+
 	# ICCID (19 digits, E.118), though some phase1 vendors use 20 :(
 	if opts.iccid is not None:
 		iccid = opts.iccid
@@ -426,6 +439,7 @@ def gen_parameters(opts):
 		'opc'	: opc,
 		'acc'	: acc,
 		'pin_adm' : pin_adm,
+		'msisdn' : opts.msisdn,
 	}
 
 
diff --git a/pySim/cards.py b/pySim/cards.py
index 802ad697..b4b5fdf3 100644
--- a/pySim/cards.py
+++ b/pySim/cards.py
@@ -658,6 +658,17 @@ class SysmoUSIMSJS1(Card):
 			r = self._scc.select_file(['3f00', '7f10'])
 			data, sw = self._scc.update_record('6f42', 1, lpad(p['smsp'], 104), force_len=True)
 
+		# EF.MSISDN
+		# TODO: Alpha Identifier (currently 'ff'O * 20)
+		# TODO: Capability/Configuration1 Record Identifier
+		# TODO: Extension1 Record Identifier
+		if p.get('msisdn') is not None:
+			msisdn = enc_msisdn(p['msisdn'])
+			data = 'ff' * 20 + msisdn + 'ff' * 2
+
+			r = self._scc.select_file(['3f00', '7f10'])
+			data, sw = self._scc.update_record('6F40', 1, data, force_len=True)
+
 	def erase(self):
 		return
 
diff --git a/pySim/utils.py b/pySim/utils.py
index 12f66b94..8420b23d 100644
--- a/pySim/utils.py
+++ b/pySim/utils.py
@@ -299,3 +299,29 @@ def dec_msisdn(ef_msisdn):
 		msisdn = '+' + msisdn
 
 	return (npi, ton, msisdn)
+
+def enc_msisdn(msisdn, npi=0x01, ton=0x03):
+	"""
+	Encode MSISDN as LHV so it can be stored to EF.MSISDN.
+	See 3GPP TS 31.102, section 4.2.26 and 4.4.2.3.
+
+	Default NPI / ToN values:
+	  - NPI: ISDN / telephony numbering plan (E.164 / E.163),
+	  - ToN: network specific or international number (if starts with '+').
+	"""
+
+	# Leading '+' indicates International Number
+	if msisdn[0] == '+':
+		msisdn = msisdn[1:]
+		ton = 0x01
+
+	# Append 'f' padding if number of digits is odd
+	if len(msisdn) % 2 > 0:
+		msisdn += 'f'
+
+	# BCD length also includes NPI/ToN header
+	bcd_len = len(msisdn) // 2 + 1
+	npi_ton = (npi & 0x0f) | ((ton & 0x07) << 4) | 0x80
+	bcd = rpad(swap_nibbles(msisdn), 10 * 2) # pad to 10 octets
+
+	return ('%02x' % bcd_len) + ('%02x' % npi_ton) + bcd
diff --git a/pysim-testdata/sysmoUSIM-SJS1.data b/pysim-testdata/sysmoUSIM-SJS1.data
index b7c1e810..c23f9f16 100644
--- a/pysim-testdata/sysmoUSIM-SJS1.data
+++ b/pysim-testdata/sysmoUSIM-SJS1.data
@@ -4,4 +4,5 @@ ICCID=1122334455667788990
 KI=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 OPC=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 IMSI=001010000000102
+MSISDN=+77776336143
 ADM=55538407
diff --git a/pysim-testdata/sysmoUSIM-SJS1.ok b/pysim-testdata/sysmoUSIM-SJS1.ok
index 6d85f38f..290c4706 100644
--- a/pysim-testdata/sysmoUSIM-SJS1.ok
+++ b/pysim-testdata/sysmoUSIM-SJS1.ok
@@ -50,7 +50,7 @@ HPLMNAcT:
 	ffffff0000 # unused
 
 ACC: 0008
-MSISDN: Can't read file -- Length of MSISDN (136 bytes) is out of range
+MSISDN (NPI=1 ToN=1): +77776336143
 AD: 00000002
 Done !
 
diff --git a/tests/pysim-test.sh b/tests/pysim-test.sh
index 0d469c9e..a22c3726 100755
--- a/tests/pysim-test.sh
+++ b/tests/pysim-test.sh
@@ -162,6 +162,7 @@ function run_test {
 	KI=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 	OPC=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 	IMSI=001010000000001
+	MSISDN=6766266
 	ADM=00000000
 	ADM_HEX=""
 	ADM_OPT="-a"
@@ -171,7 +172,7 @@ function run_test {
 		ADM_OPT="-A"
 		ADM=$ADM_HEX
 	fi
-	python $PYSIM_PROG -p $I -t $CARD_NAME -o $OPC -k $KI -x $MCC -y $MNC -i $IMSI -s $ICCID $ADM_OPT $ADM
+	python $PYSIM_PROG -p $I -t $CARD_NAME -o $OPC -k $KI -x $MCC -y $MNC -i $IMSI -s $ICCID --msisdn $MSISDN $ADM_OPT $ADM
 	check_card $I $CARD_NAME
 	echo ""
     done
diff --git a/tests/sysmoUSIM-SJS1.data.example b/tests/sysmoUSIM-SJS1.data.example
index d711dcbb..19efd157 100644
--- a/tests/sysmoUSIM-SJS1.data.example
+++ b/tests/sysmoUSIM-SJS1.data.example
@@ -4,4 +4,5 @@ ICCID=1122334455667788990
 KI=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 OPC=FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
 IMSI=001010000000102
+MSISDN=+77776336143
 ADM=12345678