diff --git a/add_certificate_modal.php b/add_certificate_modal.php
index e891b944..ba5422c2 100644
--- a/add_certificate_modal.php
+++ b/add_certificate_modal.php
@@ -1,75 +1,95 @@
 <div class="modal" id="addCertificateModal" tabindex="-1">
-  <div class="modal-dialog">
-    <div class="modal-content bg-dark">
-      <div class="modal-header">
-        <h5 class="modal-title"><i class="fa fa-fw fa-lock"></i> New Certificate</h5>
-        <button type="button" class="close text-white" data-dismiss="modal">
-          <span>&times;</span>
-        </button>
-      </div>
-      <form action="post.php" method="post" autocomplete="off">
-        <input type="hidden" name="client_id" value="<?php echo $client_id; ?>">
-        <div class="modal-body bg-white">    
-          
-          <div class="form-group">
-            <label>Certificate Name <strong class="text-danger">*</strong></label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-lock"></i></span>
-              </div>
-              <input type="text" class="form-control" name="name" placeholder="Certificate name" required autofocus>
+    <div class="modal-dialog">
+        <div class="modal-content bg-dark">
+            <div class="modal-header">
+                <h5 class="modal-title"><i class="fa fa-fw fa-lock"></i> New Certificate</h5>
+                <button type="button" class="close text-white" data-dismiss="modal">
+                    <span>&times;</span>
+                </button>
             </div>
-          </div>
+            <form action="post.php" method="post" autocomplete="off">
+                <input type="hidden" name="client_id" value="<?php echo $client_id; ?>">
+                <div class="modal-body bg-white">
 
-          <div class="form-group">
-            <label>Domain <strong class="text-danger">*</strong></label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i>&nbsp;https://</span>
-              </div>
-              <input type="text" class="form-control" name="domain" id="domain" placeholder="FQDN" required>
-              <div class="input-group-append">
-                <button type="button" class="btn btn-secondary" onclick="fetchSSL()"><i class="fas fa-fw fa-sync-alt"></i></button>
-              </div>
-            </div>
-          </div>
-          
-          <div class="form-group">
-            <label>Issued By </label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-building"></i></span>
-              </div>
-              <input type="text" class="form-control" name="issued_by" id="issued_by" placeholder="Issued By">
-            </div>
-          </div>
-        
-          <div class="form-group">
-            <label>Expire Date</label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-calendar"></i></span>
-              </div>
-              <input type="date" class="form-control" name="expire" id="expire">
-            </div>
-          </div>
+                    <div class="form-group">
+                        <label>Certificate Name <strong class="text-danger">*</strong></label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-lock"></i></span>
+                            </div>
+                            <input type="text" class="form-control" name="name" placeholder="Certificate name" required autofocus>
+                        </div>
+                    </div>
 
-          <div class="form-group">
-            <label>Public Key </label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-key"></i></span>
-              </div>
-              <textarea class="form-control" name="public_key" id="public_key" placeholder="-----BEGIN CERTIFICATE-----"></textarea>
-            </div>
-          </div>
+                    <div class="form-group">
+                        <label>Domain <strong class="text-danger">*</strong></label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i>&nbsp;https://</span>
+                            </div>
+                            <input type="text" class="form-control" name="domain" id="domain" placeholder="FQDN" required>
+                            <div class="input-group-append">
+                                <button type="button" class="btn btn-secondary" onclick="fetchSSL()"><i class="fas fa-fw fa-sync-alt"></i></button>
+                            </div>
+                        </div>
+                    </div>
 
+                    <div class="form-group">
+                        <label>Issued By </label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-building"></i></span>
+                            </div>
+                            <input type="text" class="form-control" name="issued_by" id="issued_by" placeholder="Issued By">
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Expire Date</label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-calendar"></i></span>
+                            </div>
+                            <input type="date" class="form-control" name="expire" id="expire">
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Public Key </label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-key"></i></span>
+                            </div>
+                            <textarea class="form-control" name="public_key" id="public_key" placeholder="-----BEGIN CERTIFICATE-----"></textarea>
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Domain</label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i></span>
+                            </div>
+                            <select class="form-control select2" name="domain_id" required>
+                                <option value="">- Domain -</option>
+                                <?php
+                                $domains_sql = mysqli_query($mysqli, "SELECT * FROM domains WHERE domain_client_id = '$client_id'");
+                                while($domain_row = mysqli_fetch_array($domains_sql)){
+                                    $domain_id = $domain_row['domain_id'];
+                                    $domain_name = $domain_row['domain_name'];
+                                    echo "<option value=\"$domain_id\">$domain_name</option>";
+                                }
+                                ?>
+                            </select>
+                        </div>
+                    </div>
+                </div>
+
+                <div class="modal-footer bg-white">
+                    <button type="button" class="btn btn-secondary" data-dismiss="modal">Cancel</button>
+                    <button type="submit" name="add_certificate" class="btn btn-primary">Save</button>
+                </div>
+            </form>
         </div>
-        <div class="modal-footer bg-white">
-          <button type="button" class="btn btn-secondary" data-dismiss="modal">Cancel</button>
-          <button type="submit" name="add_certificate" class="btn btn-primary">Save</button>
-        </div>
-      </form>
     </div>
-  </div>
 </div>
\ No newline at end of file
diff --git a/client_certificates.php b/client_certificates.php
index ecdf67b5..8c935403 100644
--- a/client_certificates.php
+++ b/client_certificates.php
@@ -100,6 +100,7 @@ $num_rows = mysqli_fetch_row(mysqli_query($mysqli,"SELECT FOUND_ROWS()"));
             $certificate_expire = $row['certificate_expire'];
             $certificate_updated_at = $row['certificate_updated_at'];
             $certificate_public_key = $row['certificate_public_key'];
+            $certificate_domain_id = $row['certificate_domain_id'];
 
           ?>
           <tr>
diff --git a/db.sql b/db.sql
index 6b60f3c3..a81b30be 100644
--- a/db.sql
+++ b/db.sql
@@ -218,6 +218,7 @@ CREATE TABLE `certificates` (
   `certificate_created_at` datetime NOT NULL,
   `certificate_updated_at` datetime DEFAULT NULL,
   `certificate_archived_at` datetime DEFAULT NULL,
+  `certificate_domain_id` int(11) DEFAULT NULL,
   `certificate_client_id` int(11) NOT NULL,
   `company_id` int(11) NOT NULL,
   PRIMARY KEY (`certificate_id`)
diff --git a/edit_certificate_modal.php b/edit_certificate_modal.php
index b1689408..55a34728 100644
--- a/edit_certificate_modal.php
+++ b/edit_certificate_modal.php
@@ -1,75 +1,99 @@
 <div class="modal" id="editCertificateModal<?php echo $certificate_id; ?>" tabindex="-1">
-  <div class="modal-dialog">
-    <div class="modal-content bg-dark">
-      <div class="modal-header">
-        <h5 class="modal-title"><i class="fa fa-fw fa-lock"></i> <?php echo $certificate_name ?></h5>
-        <button type="button" class="close text-white" data-dismiss="modal">
-          <span>&times;</span>
-        </button>
-      </div>
-      <form action="post.php" method="post" autocomplete="off">
-        <input type="hidden" name="certificate_id" value="<?php echo $certificate_id; ?>">
-        <div class="modal-body bg-white">    
-          
-          <div class="form-group">
-            <label>Certificate Name <strong class="text-danger">*</strong></label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-lock"></i></span>
-              </div>
-              <input type="text" class="form-control" name="name" placeholder="Certificate name" value="<?php echo $certificate_name; ?>" required>
+    <div class="modal-dialog">
+        <div class="modal-content bg-dark">
+            <div class="modal-header">
+                <h5 class="modal-title"><i class="fa fa-fw fa-lock"></i> <?php echo $certificate_name ?></h5>
+                <button type="button" class="close text-white" data-dismiss="modal">
+                    <span>&times;</span>
+                </button>
             </div>
-          </div>
+            <form action="post.php" method="post" autocomplete="off">
+                <input type="hidden" name="certificate_id" value="<?php echo $certificate_id; ?>">
+                <div class="modal-body bg-white">
 
-          <div class="form-group">
-            <label>Domain <strong class="text-danger">*</strong></label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i>&nbsp;https://</span>
-              </div>
-              <input type="text" class="form-control" name="domain" placeholder="Domain" id="domain"  value="<?php echo $certificate_domain; ?>" required>
-              <div class="input-group-append">
-                <button type="button" class="btn btn-secondary" onclick="fetchSSL()"><i class="fas fa-fw fa-sync-alt"></i></button>
-              </div>
-            </div>
-          </div>
+                    <div class="form-group">
+                        <label>Certificate Name <strong class="text-danger">*</strong></label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-lock"></i></span>
+                            </div>
+                            <input type="text" class="form-control" name="name" placeholder="Certificate name" value="<?php echo $certificate_name; ?>" required>
+                        </div>
+                    </div>
 
-          <div class="form-group">
-            <label>Issued By</label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-building"></i></span>
-              </div>
-              <input type="text" class="form-control" name="issued_by" placeholder="Issued By" id="issued_by" value="<?php echo $certificate_issued_by; ?>">
-            </div>
-          </div>
-        
-          <div class="form-group">
-            <label>Expire Date</label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-calendar"></i></span>
-              </div>
-              <input type="date" class="form-control" name="expire" id="expire" value="<?php echo $certificate_expire; ?>">
-            </div>
-          </div>
+                    <div class="form-group">
+                        <label>Domain <strong class="text-danger">*</strong></label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i>&nbsp;https://</span>
+                            </div>
+                            <input type="text" class="form-control" name="domain" placeholder="Domain" id="domain"  value="<?php echo $certificate_domain; ?>" required>
+                            <div class="input-group-append">
+                                <button type="button" class="btn btn-secondary" onclick="fetchSSL()"><i class="fas fa-fw fa-sync-alt"></i></button>
+                            </div>
+                        </div>
+                    </div>
 
-          <div class="form-group">
-            <label>Public Key </label>
-            <div class="input-group">
-              <div class="input-group-prepend">
-                <span class="input-group-text"><i class="fa fa-fw fa-key"></i></span>
-              </div>
-              <textarea class="form-control" name="public_key" id="public_key"><?php echo $certificate_public_key; ?></textarea>
-            </div>
-          </div>
+                    <div class="form-group">
+                        <label>Issued By</label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-building"></i></span>
+                            </div>
+                            <input type="text" class="form-control" name="issued_by" placeholder="Issued By" id="issued_by" value="<?php echo $certificate_issued_by; ?>">
+                        </div>
+                    </div>
 
+                    <div class="form-group">
+                        <label>Expire Date</label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-calendar"></i></span>
+                            </div>
+                            <input type="date" class="form-control" name="expire" id="expire" value="<?php echo $certificate_expire; ?>">
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Public Key </label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-key"></i></span>
+                            </div>
+                            <textarea class="form-control" name="public_key" id="public_key"><?php echo $certificate_public_key; ?></textarea>
+                        </div>
+                    </div>
+
+                    <div class="form-group">
+                        <label>Domain</label>
+                        <div class="input-group">
+                            <div class="input-group-prepend">
+                                <span class="input-group-text"><i class="fa fa-fw fa-globe"></i></span>
+                            </div>
+                            <select class="form-control select2" name="domain_id" required>
+                                <option value="">- Domain -</option>
+                                <?php
+                                $domains_sql = mysqli_query($mysqli, "SELECT * FROM domains WHERE domain_client_id = '$client_id'");
+                                while($domain_row = mysqli_fetch_array($domains_sql)){
+                                    $domain_id = $domain_row['domain_id'];
+                                    $domain_name = $domain_row['domain_name'];
+                                    if($certificate_domain_id == $domain_id){
+                                        echo "<option value=\"$domain_id\" selected>$domain_name</option>";
+                                    }
+                                    else{
+                                        echo "<option value=\"$domain_id\">$domain_name</option>";
+                                    }
+                                }
+                                ?>
+                            </select>
+                        </div>
+                    </div>
+                </div>
+                <div class="modal-footer bg-white">
+                    <button type="button" class="btn btn-secondary" data-dismiss="modal">Cancel</button>
+                    <button type="submit" name="edit_certificate" class="btn btn-primary">Save</button>
+                </div>
+            </form>
         </div>
-        <div class="modal-footer bg-white">
-          <button type="button" class="btn btn-secondary" data-dismiss="modal">Cancel</button>
-          <button type="submit" name="edit_certificate" class="btn btn-primary">Save</button>
-        </div>
-      </form>
     </div>
-  </div>
 </div>
\ No newline at end of file
diff --git a/post.php b/post.php
index 19571196..a0fe9f99 100644
--- a/post.php
+++ b/post.php
@@ -4959,6 +4959,7 @@ if(isset($_POST['add_certificate'])){
     $issued_by = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['issued_by'])));
     $expire = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['expire'])));
     $public_key = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['public_key'])));
+    $domain_id = intval($_POST['domain_id']);
 
     // Parse public key data for a manually provided public key
     if(!empty($public_key) && (empty($expire) && empty($issued_by))) {
@@ -4974,7 +4975,7 @@ if(isset($_POST['add_certificate'])){
         $expire = "0000-00-00";
     }
 
-    mysqli_query($mysqli,"INSERT INTO certificates SET certificate_name = '$name', certificate_domain = '$domain', certificate_issued_by = '$issued_by', certificate_expire = '$expire', certificate_created_at = NOW(), certificate_public_key = '$public_key', certificate_client_id = $client_id, company_id = $session_company_id");
+    mysqli_query($mysqli,"INSERT INTO certificates SET certificate_name = '$name', certificate_domain = '$domain', certificate_issued_by = '$issued_by', certificate_expire = '$expire', certificate_created_at = NOW(), certificate_public_key = '$public_key', certificate_domain_id = $domain_id, certificate_client_id = $client_id, company_id = $session_company_id");
 
     //Logging
     mysqli_query($mysqli,"INSERT INTO logs SET log_type = 'Certificate', log_action = 'Created', log_description = '$name', log_created_at = NOW(), company_id = $session_company_id, log_user_id = $session_user_id");
@@ -4993,6 +4994,7 @@ if(isset($_POST['edit_certificate'])){
     $issued_by = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['issued_by'])));
     $expire = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['expire'])));
     $public_key = trim(strip_tags(mysqli_real_escape_string($mysqli,$_POST['public_key'])));
+    $domain_id = intval($_POST['domain_id']);
 
     // Parse public key data for a manually provided public key
     if(!empty($public_key) && (empty($expire) && empty($issued_by))) {
@@ -5008,7 +5010,7 @@ if(isset($_POST['edit_certificate'])){
         $expire = "0000-00-00";
     }
 
-    mysqli_query($mysqli,"UPDATE certificates SET certificate_name = '$name', certificate_domain = '$domain', certificate_issued_by = '$issued_by', certificate_expire = '$expire', certificate_updated_at = NOW(), certificate_public_key = '$public_key' WHERE certificate_id = $certificate_id AND company_id = $session_company_id");
+    mysqli_query($mysqli,"UPDATE certificates SET certificate_name = '$name', certificate_domain = '$domain', certificate_issued_by = '$issued_by', certificate_expire = '$expire', certificate_updated_at = NOW(), certificate_public_key = '$public_key', certificate_domain_id = '$domain_id' WHERE certificate_id = $certificate_id AND company_id = $session_company_id");
 
     //Logging
     mysqli_query($mysqli,"INSERT INTO logs SET log_type = 'Certificate', log_action = 'Modified', log_description = '$name', log_created_at = NOW(), company_id = $session_company_id, log_user_id = $session_user_id");