diff --git a/src/main/java/com/smartystreets/api/us_reverse_geo/Address.java b/src/main/java/com/smartystreets/api/us_reverse_geo/Address.java
index 6e8be06..368e9c4 100644
--- a/src/main/java/com/smartystreets/api/us_reverse_geo/Address.java
+++ b/src/main/java/com/smartystreets/api/us_reverse_geo/Address.java
@@ -11,6 +11,7 @@ public class Address implements Serializable {
     private String city;
     private String stateAbbreviation;
     private String zipCode;
+    private String source;
 
     //endregion
 
@@ -24,4 +25,7 @@ public class Address implements Serializable {
     @JsonProperty("zipcode")
     public String getZipCode() { return this.zipCode; }
 
+    @JsonProperty("source")
+    public String getSource() { return this.source; }
+
 }
diff --git a/src/main/java/com/smartystreets/api/us_reverse_geo/Client.java b/src/main/java/com/smartystreets/api/us_reverse_geo/Client.java
index cec1279..958c5c4 100644
--- a/src/main/java/com/smartystreets/api/us_reverse_geo/Client.java
+++ b/src/main/java/com/smartystreets/api/us_reverse_geo/Client.java
@@ -24,6 +24,7 @@ public void send(Lookup lookup) throws SmartyException, IOException, Interrupted
         DecimalFormat decimalFormat = new DecimalFormat("#.########");
         request.putParameter("latitude", decimalFormat.format(lookup.getLatitude()));
         request.putParameter("longitude", decimalFormat.format(lookup.getLongitude()));
+        request.putParameter("source", getSource();
 
         Response httpResponse = this.sender.send(request);
 
diff --git a/src/main/java/com/smartystreets/api/us_reverse_geo/Lookup.java b/src/main/java/com/smartystreets/api/us_reverse_geo/Lookup.java
index ff43586..fb6706a 100644
--- a/src/main/java/com/smartystreets/api/us_reverse_geo/Lookup.java
+++ b/src/main/java/com/smartystreets/api/us_reverse_geo/Lookup.java
@@ -8,6 +8,7 @@ public class Lookup implements Serializable {
 
     private double latitude;
     private double longitude;
+    private String source;
 
     private SmartyResponse response;
 
@@ -15,16 +16,19 @@ public class Lookup implements Serializable {
 
     public Lookup() { this.response = new SmartyResponse(); }
 
-    public Lookup(double latitude, double longitude) {
+    public Lookup(double latitude, double longitude, String source) {
         this();
         this.latitude = latitude;
         this.longitude = longitude;
+        this.source = source;
     }
 
     public Double getLatitude() { return this.latitude; }
 
     public Double getLongitude() { return this.longitude; }
 
+    public String getSource() { return this.source; }
+
     public SmartyResponse getResponse() { return this.response; }
 
     public void setResponse(SmartyResponse response) {