diff --git a/CRM/Core/Payment/OmnipayMultiProcessor.php b/CRM/Core/Payment/OmnipayMultiProcessor.php
index 077f24894..b7fd5cf04 100644
--- a/CRM/Core/Payment/OmnipayMultiProcessor.php
+++ b/CRM/Core/Payment/OmnipayMultiProcessor.php
@@ -283,7 +283,11 @@ public function buildForm(&$form) {
       'paymentProcessorId' => $this->_paymentProcessor['id'], 'currency' => $form->getCurrency(),
       'is_test' => $this->_is_test,
       'title' => $form->getTitle(),
+      'validate' => [],
     ];
+    if (is_a($form, 'CRM_Contribute_Form_Contribution_Main')) {
+      $jsVariables['validate'] = ['entity' => 'ContributionPage', 'params' => ['id' =>  $form->_id, 'action' => 'submit']];
+    }
     $clientSideCredentials = $this->getProcessorTypeMetadata('client_side_credentials');
     if ($clientSideCredentials) {
       foreach ($clientSideCredentials as $key => $clientSideKey) {
diff --git a/Metadata/js/omnipay_PaypalRest.js b/Metadata/js/omnipay_PaypalRest.js
index b15f56659..be0897f6f 100644
--- a/Metadata/js/omnipay_PaypalRest.js
+++ b/Metadata/js/omnipay_PaypalRest.js
@@ -12,6 +12,7 @@
           var paymentAmount = calculateTotalFee();
           var isRecur = $('#is_recur').is(":checked");
           var recurText = isRecur ? ' recurring' : '';
+          var validate = CRM.vars.omnipay.validate;
 
           return new Promise(function (resolve, reject) {
             CRM.api3('PaymentProcessor', 'preapprove', {
@@ -24,6 +25,7 @@
                 'frequency_unit' : frequencyUnit,
                 'frequency_interval' : frequencyInterval,
                 'description' : CRM.vars.omnipay.title + ' ' + CRM.formatMoney(paymentAmount) + recurText,
+                'validate' : validate,
               }
             ).then(function (result) {
                 if (result['is_error'] === 1) {
diff --git a/api/v3/PaymentProcessor/Preapprove.php b/api/v3/PaymentProcessor/Preapprove.php
index 766799cc5..892bfa580 100644
--- a/api/v3/PaymentProcessor/Preapprove.php
+++ b/api/v3/PaymentProcessor/Preapprove.php
@@ -9,6 +9,10 @@
  * @throws CiviCRM_API3_Exception
  */
 function civicrm_api3_payment_processor_preapprove($params) {
+  if (!empty($params['validate'])) {
+    $validation = civicrm_api3($params['validate']['entity'], 'validate', array_merge($params['validate']['params'], $params));
+    // @todo - do something clever if it fails
+  }
   $processor = Civi\Payment\System::singleton()->getById($params['payment_processor_id']);
   $processor->setPaymentProcessor(civicrm_api3('PaymentProcessor', 'getsingle', array('id' => $params['payment_processor_id'])));
   $result = $processor->doPreApproval($params);
diff --git a/tests/phpunit/api/PreApproveTest.php b/tests/phpunit/api/PreApproveTest.php
index 86e3c4a8c..e326a4d75 100644
--- a/tests/phpunit/api/PreApproveTest.php
+++ b/tests/phpunit/api/PreApproveTest.php
@@ -67,6 +67,7 @@ public function testPreApproveRest() {
       'component' => 'contribute',
       'version' => 3,
       'email' => 'blah@example.org',
+      'validate' => []
     ])['values'][0];
     $this->assertEquals('EC-9T988732661526452', $preApproval['token']);