diff --git a/src/main/java/org/jenkinsci/plugins/github_branch_source/GitHubOrgWebHook.java b/src/main/java/org/jenkinsci/plugins/github_branch_source/GitHubOrgWebHook.java
index d027766d0..97f9350d7 100644
--- a/src/main/java/org/jenkinsci/plugins/github_branch_source/GitHubOrgWebHook.java
+++ b/src/main/java/org/jenkinsci/plugins/github_branch_source/GitHubOrgWebHook.java
@@ -52,19 +52,16 @@ public class GitHubOrgWebHook {
           GHEvent.PULL_REQUEST_REVIEW_COMMENT);
 
   public static void register(GitHub hub, String orgName) throws IOException {
-    String rootUrl = System.getProperty("jenkins.hook.url");
-    if (rootUrl == null) {
-      rootUrl = Jenkins.get().getRootUrl();
-    }
-    if (rootUrl == null) {
+    String url = getWebhookUrl();
+    if (url == null) {
       return;
     }
+
     GHUser u = hub.getUser(orgName);
     FileBoolean orghook = new FileBoolean(getTrackingFile(orgName));
     if (orghook.isOff()) {
       try {
         GHOrganization org = hub.getOrganization(orgName);
-        String url = rootUrl + "github-webhook/";
         boolean found = false;
         for (GHHook hook : org.getHooks()) {
           if (hook.getConfig().get("url").equals(url)) {
@@ -104,16 +101,16 @@ private static File getTrackingFile(String orgName) {
   }
 
   public static void deregister(GitHub hub, String orgName) throws IOException {
-    String rootUrl = Jenkins.get().getRootUrl();
-    if (rootUrl == null) {
+    String url = getWebhookUrl();
+    if (url == null) {
       return;
     }
+
     GHUser u = hub.getUser(orgName);
     FileBoolean orghook = new FileBoolean(getTrackingFile(orgName));
     if (orghook.isOn()) {
       try {
         GHOrganization org = hub.getOrganization(orgName);
-        String url = rootUrl + "github-webhook/";
         for (GHHook hook : org.getHooks()) {
           if (hook.getConfig().get("url").equals(url)) {
             hook.delete();
@@ -144,4 +141,16 @@ public static void deregister(GitHub hub, String orgName) throws IOException {
       }
     }
   }
+
+  private static String getWebhookUrl() {
+    String rootUrl = System.getProperty("jenkins.hook.url");
+    if (rootUrl == null) {
+      rootUrl = Jenkins.get().getRootUrl();
+    }
+    if (rootUrl == null) {
+      return rootUrl;
+    }
+
+    return rootUrl + "github-webhook/";
+  }
 }