diff --git a/configs/appcfg/xinit_template b/configs/appcfg/xinit_template
index f9a7958..c497864 100644
--- a/configs/appcfg/xinit_template
+++ b/configs/appcfg/xinit_template
@@ -24,6 +24,11 @@ amixer set "Line Out" 50%
 # Play a funky startup tune
 #mpv --quiet --no-video ~/welcome.ogg &
 
+# You will sometime get SMS or calls from not
+#  country code prefixed phone numbers. To ensure
+#  we match your contacts, we will use this one.
+#export DEFAULT_NUMBER_PREFIX=+33
+
 # turn on modemmonitor on login
 # Note: if the modemmonitor is not on you can
 # not receive texts/calls!
diff --git a/scripts/core/sxmo_contactmenu.sh b/scripts/core/sxmo_contactmenu.sh
index 5655192..2cbe78e 100755
--- a/scripts/core/sxmo_contactmenu.sh
+++ b/scripts/core/sxmo_contactmenu.sh
@@ -3,9 +3,23 @@
 # shellcheck source=scripts/core/sxmo_common.sh
 . "$(dirname "$0")/sxmo_common.sh"
 
+valid_number() {
+	number="$(echo "$1" | sed "s/^0\([0-9]\{9\}\)$/${DEFAULT_NUMBER_PREFIX:-0}\1/")"
+
+	if echo "$number" | grep -q "^+[0-9]\{11\}$"; then
+		echo "$number"
+	else
+		notify-send "\"$number\" is not a valid phone number"
+		notify-send "Valid format is \"+[0-9]{11}\""
+	fi
+}
+
 newcontact() {
 	name="$(echo | sxmo_dmenu_with_kb.sh -c -l 2 -p "$icon_usr Name")"
-	number="$(echo | sxmo_dmenu_with_kb.sh -c -l 2 -p "$icon_phl Number")"
+	while [ -z "$number" ]; do
+		number="$(echo | sxmo_dmenu_with_kb.sh -c -l 2 -p "$icon_phl Number")"
+		number="$(valid_number "$number")"
+	done
 
 	PICKED="$number	$name" # now act like if we picked this new contact
 	echo "$PICKED" >> "$CONTACTFILE"
@@ -35,18 +49,22 @@ editcontactnumber() {
 	oldname="$(echo "$1" | cut -d"	" -f2)"
 
 	ENTRIES="$(printf %b "Old number: $oldnumber")"
-	PICKED="$(
-		echo "$ENTRIES" |
-		sxmo_dmenu_with_kb.sh -c -l 3 -p "$icon_edt Edit Contact"
-	)"
-
-	if ! echo "$PICKED" | grep -q "^Old number: "; then
-		newcontact="$PICKED	$oldname"
-		sed -i "s/^$1$/$newcontact/" "$CONTACTFILE"
-		set -- "$newcontact"
-	fi
+	PICKED= # already used var name
+	while [ -z "$PICKED" ]; do
+		PICKED="$(
+			echo "$ENTRIES" |
+			sxmo_dmenu_with_kb.sh -c -l 3 -p "$icon_edt Edit Contact"
+		)"
+		if echo "$PICKED" | grep -q "^Old number: "; then
+			editcontact "$1"
+			return
+		fi
+		PICKED="$(valid_number "$PICKED")"
+	done
 
-	editcontact "$1"
+	newcontact="$PICKED	$oldname"
+	sed -i "s/^$1$/$newcontact/" "$CONTACTFILE"
+	editcontact "$newcontact"
 }
 
 deletecontact() {
diff --git a/scripts/core/sxmo_contacts.sh b/scripts/core/sxmo_contacts.sh
index 85c1972..886dc22 100755
--- a/scripts/core/sxmo_contacts.sh
+++ b/scripts/core/sxmo_contacts.sh
@@ -20,6 +20,7 @@ contacts() {
 	grep -q . "$CONTACTSFILE" || echo " " > "$CONTACTSFILE"
 	RECENTCONTACTEDNUMBERSREVCHRON="$(
 		cut -f3 "$LOGFILE" |
+		sed "s/^0\([0-9]\{9\}\)$/${DEFAULT_NUMBER_PREFIX:-0}\1/" |
 		tac |
 		awk '!($0 in a){a[$0]; print}' |
 		sed '/^[[:space:]]*$/d'
diff --git a/scripts/modem/sxmo_modemmonitor.sh b/scripts/modem/sxmo_modemmonitor.sh
index d5ba98e..bbac2fc 100755
--- a/scripts/modem/sxmo_modemmonitor.sh
+++ b/scripts/modem/sxmo_modemmonitor.sh
@@ -47,11 +47,9 @@ lookupcontactname() {
 	if [ "$1" = "--" ]; then
 		echo "Unknown number"
 	else
-		NUMBER="$1"
+		NUMBER="$(echo "$1" | sed "s/^0\([0-9]\{9\}\)$/${DEFAULT_NUMBER_PREFIX:-0}\1/")"
 		CONTACT=$(sxmo_contacts.sh --all |
-			grep "$NUMBER:" | #this is not an exact match but a suffix match
-							  #which also works if the + and country code are missing
-							  #but may lead to false positives in rare cases (short numbers)
+			grep "^$NUMBER:" |
 			cut -d':' -f 2 |
 			sed 's/^[ \t]*//;s/[ \t]*$//' #strip leading/trailing whitespace
 		)