diff --git a/libsignal/service/src/main/java/org/whispersystems/signalservice/api/util/PhoneNumberFormatter.java b/libsignal/service/src/main/java/org/whispersystems/signalservice/api/util/PhoneNumberFormatter.java
index fa4ddfc826..b21ecc8329 100644
--- a/libsignal/service/src/main/java/org/whispersystems/signalservice/api/util/PhoneNumberFormatter.java
+++ b/libsignal/service/src/main/java/org/whispersystems/signalservice/api/util/PhoneNumberFormatter.java
@@ -147,7 +147,7 @@ public class PhoneNumberFormatter {
 
     return "+"                                                     +
         countryCode.replaceAll("[^0-9]", "").replaceAll("^0*", "") +
-        number.replaceAll("[^0-9]", "");
+        (number != null ? number.replaceAll("[^0-9]", "") : "");
   }
 
   public static String getInternationalFormatFromE164(String e164number) {