diff --git a/README.md b/README.md
index 1fdd385..852cae2 100644
--- a/README.md
+++ b/README.md
@@ -7,5 +7,5 @@ Common functionality in goflow and courier.
 You can run all the tests (excluding tests in vendor packages) with:
 
 ```
-% go test $(go list ./... | grep -v /vendor/)
+% go test github.com/nyaruka/gocommon/...
 ```
diff --git a/urns/urns.go b/urns/urns.go
index c6954a3..380640a 100644
--- a/urns/urns.go
+++ b/urns/urns.go
@@ -74,6 +74,7 @@ func IsValidScheme(scheme string) bool {
 }
 
 var nonTelCharsRegex = regexp.MustCompile(`[^0-9a-z]`)
+var telRegex = regexp.MustCompile(`^\+?[a-zA-Z0-9]{3,16}$`)
 var twitterHandleRegex = regexp.MustCompile(`^[a-zA-Z0-9_]{1,15}$`)
 var emailRegex = regexp.MustCompile(`^[^\s@]+@[^\s@]+$`)
 var viberRegex = regexp.MustCompile(`^[a-zA-Z0-9_=/+]{1,24}$`)
@@ -186,10 +187,10 @@ func (u URN) Validate() error {
 	switch scheme {
 	case TelScheme:
 		// validate is possible phone number
-		_, err := phonenumbers.Parse(path, "")
-		if err != nil {
-			return err
+		if !telRegex.MatchString(path) {
+			return fmt.Errorf("invalid tel number: %s", path)
 		}
+
 	case TwitterScheme:
 		// validate twitter URNs look like handles
 		if !twitterHandleRegex.MatchString(path) {
diff --git a/urns/urns_test.go b/urns/urns_test.go
index 618b5b9..308dc17 100644
--- a/urns/urns_test.go
+++ b/urns/urns_test.go
@@ -203,15 +203,15 @@ func TestValidate(t *testing.T) {
 
 		// valid tel numbers
 		{"tel:+250788383383", ""},
-		{"tel:+23761234567", ""},  // old Cameroon format
-		{"tel:+237661234567", ""}, // new Cameroon format
 		{"tel:+250788383383", ""},
-
-		{"tel:+250123", ""}, // invalid but parsed we accept it then
+		{"tel:+250123", ""},
+		{"tel:1337", ""},
+		{"tel:PRIZES", ""},
 
 		// invalid tel numbers
-		{"tel:0788383383", "invalid country code"}, // no country
-		{"tel:MTN", "phone number supplied was empty"},
+		{"tel:07883 83383", "invalid tel number"},       // can't have spaces
+		{"tel:12", "invalid tel number"},                // too short
+		{"tel:12345678901234567", "invalid tel number"}, // too long
 
 		// twitter handles
 		{"twitter:jimmyjo", ""},
@@ -287,15 +287,19 @@ func TestTelURNs(t *testing.T) {
 		{"+250788383383", "", "tel:+250788383383", false},
 		{"250788383383", "", "tel:+250788383383", false},
 		{"(917)992-5253", "US", "tel:+19179925253", false},
+		{"(917) 992 - 5253", "US", "tel:+19179925253", false},
 		{"19179925253", "", "tel:+19179925253", false},
 		{"+62877747666", "", "tel:+62877747666", false},
 		{"62877747666", "ID", "tel:+62877747666", false},
 		{"0877747666", "ID", "tel:+62877747666", false},
 		{"07531669965", "GB", "tel:+447531669965", false},
-		{"12345", "RW", "", true},
-		{"0788383383", "", "", true},
-		{"0788383383", "ZZ", "", true},
-		{"MTN", "RW", "", true},
+		{"12345", "RW", "tel:12345", false},
+		{"0788383383", "", "tel:0788383383", false},
+		{"0788383383", "ZZ", "tel:0788383383", false},
+		{"PRIZES", "RW", "tel:prizes", false},
+		{"PRIZES!", "RW", "tel:prizes", false},
+		{"1", "RW", "", true},
+		{"123456789012345678901234567890", "RW", "", true},
 	}
 
 	for _, tc := range testCases {