diff --git a/Sources/SmartyStreets/SmartyRequest.swift b/Sources/SmartyStreets/SmartyRequest.swift
index 3ce788d..81e397e 100644
--- a/Sources/SmartyStreets/SmartyRequest.swift
+++ b/Sources/SmartyStreets/SmartyRequest.swift
@@ -54,7 +54,9 @@ public class SmartyRequest {
     }
     
     func urlEncode(value: String) -> String {
-        return value.addingPercentEncoding(withAllowedCharacters: .urlPathAllowed)!
+        var allowedCharacters = CharacterSet.urlPathAllowed
+        allowedCharacters.remove(charactersIn: USAutocompleteProClient.arrayItemsSeparator)
+        return value.addingPercentEncoding(withAllowedCharacters: allowedCharacters)!
     }
     
     func setPayload(payload:Data) {
diff --git a/Sources/SmartyStreets/USAutocompletePro/USAutocompleteProClient.swift b/Sources/SmartyStreets/USAutocompletePro/USAutocompleteProClient.swift
index 00c417f..de0faaf 100644
--- a/Sources/SmartyStreets/USAutocompletePro/USAutocompleteProClient.swift
+++ b/Sources/SmartyStreets/USAutocompletePro/USAutocompleteProClient.swift
@@ -2,7 +2,9 @@ import Foundation
 
 public class USAutocompleteProClient: NSObject {
     //    It is recommended to instantiate this class using SSClientBuilder
-    
+
+    static let arrayItemsSeparator = ";"
+
     var sender:SmartySender
     public var serializer:SmartySerializer
     
@@ -65,6 +67,6 @@ public class USAutocompleteProClient: NSObject {
             return String()
         }
         
-        return list.joined(separator: ";")
+        return list.joined(separator: Self.arrayItemsSeparator)
     }
 }
diff --git a/Tests/SmartyStreetsTests/SmartyRequestTests.swift b/Tests/SmartyStreetsTests/SmartyRequestTests.swift
index e964ffb..8a5169f 100644
--- a/Tests/SmartyStreetsTests/SmartyRequestTests.swift
+++ b/Tests/SmartyStreetsTests/SmartyRequestTests.swift
@@ -44,4 +44,10 @@ class SmartyRequestTests: XCTestCase {
         XCTAssertEqual(url, "https://fakesearch.com/lookup?street=Parks%20Blvd")
     }
     
+    func testGetURLWithURLEncodedArray() {
+        smartyRequest.urlPrefix = "https://fakesearch.com/lookup?"
+        smartyRequest.setValue(value: "abc;def", HTTPParameterField: "array")
+        let url = smartyRequest.getUrl()
+        XCTAssertEqual(url, "https://fakesearch.com/lookup?array=abc%3Bdef")
+    }
 }