diff --git a/CRM/Contribute/BAO/Contribution.php b/CRM/Contribute/BAO/Contribution.php
index 88ef2e87180d..dc7a4f208f41 100644
--- a/CRM/Contribute/BAO/Contribution.php
+++ b/CRM/Contribute/BAO/Contribution.php
@@ -4000,7 +4000,8 @@ public static function addActivityForPayment($entityObj, $trxnObj, $activityType
    *
    * @return mixed
    */
-  public static function getPaymentInfo($id, $component, $getTrxnInfo = FALSE, $usingLineTotal = FALSE) {
+  public static function getPaymentInfo($id, $component = 'contribution', $getTrxnInfo = FALSE, $usingLineTotal = FALSE) {
+    // @todo deprecate passing in component - always call with contribution.
     if ($component == 'event') {
       $entity = 'participant';
       $entityTable = 'civicrm_participant';
diff --git a/CRM/Core/BAO/FinancialTrxn.php b/CRM/Core/BAO/FinancialTrxn.php
index e6070ebfb1f4..edef5913887b 100644
--- a/CRM/Core/BAO/FinancialTrxn.php
+++ b/CRM/Core/BAO/FinancialTrxn.php
@@ -454,6 +454,7 @@ public static function getPartialPaymentWithType($entityId, $entityName = 'parti
       return $value;
     }
 
+    // @todo - deprecate passing in entity & type - just figure out contribution id FIRST
     if ($entityName == 'participant') {
       $contributionId = CRM_Core_DAO::getFieldValue('CRM_Event_DAO_ParticipantPayment', $entityId, 'contribution_id', 'participant_id');
     }
diff --git a/CRM/Financial/BAO/Payment.php b/CRM/Financial/BAO/Payment.php
index 656f2a03e4dd..2897ee1526ea 100644
--- a/CRM/Financial/BAO/Payment.php
+++ b/CRM/Financial/BAO/Payment.php
@@ -117,4 +117,158 @@ public static function create($params) {
     return $trxn;
   }
 
+  /**
+   * Send an email confirming a payment that has been received.
+   *
+   * @param array $params
+   *
+   * @return array
+   */
+  public static function sendConfirmation($params) {
+
+    $entities = self::loadRelatedEntities($params['id']);
+    $sendTemplateParams = array(
+      'groupName' => 'msg_tpl_workflow_contribution',
+      'valueName' => 'payment_or_refund_notification',
+      'PDFFilename' => ts('notification') . '.pdf',
+      'contactId' => $entities['contact']['id'],
+      'toName' => $entities['contact']['display_name'],
+      'toEmail' => $entities['contact']['email'],
+      'tplParams' => self::getConfirmationTemplateParameters($entities),
+    );
+    return CRM_Core_BAO_MessageTemplate::sendTemplate($sendTemplateParams);
+  }
+
+  /**
+   * Load entities related to the current payment id.
+   *
+   * This gives us all the data we need to send an email confirmation but avoiding
+   * getting anything not tested for the confirmations. We retrieve the 'full' event as
+   * it has been traditionally assigned in full.
+   *
+   * @param int $id
+   *
+   * @return array
+   *   - contact = ['id' => x, 'display_name' => y, 'email' => z]
+   *   - event = [.... full event details......]
+   *   - contribution = ['id' => x],
+   *   - payment = [payment info + payment summary info]
+   */
+  protected static function loadRelatedEntities($id) {
+    $entities = [];
+    $contributionID = (int) civicrm_api3('EntityFinancialTrxn', 'getvalue', [
+      'financial_trxn_id' => $id,
+      'entity_table' => 'civicrm_contribution',
+      'return' => 'entity_id',
+    ]);
+    $entities['contribution'] = ['id' => $contributionID];
+    $entities['payment'] = array_merge(civicrm_api3('FinancialTrxn', 'getsingle', ['id' => $id]),
+      CRM_Contribute_BAO_Contribution::getPaymentInfo($contributionID)
+    );
+
+    $contactID = self::getPaymentContactID($contributionID);
+    list($displayName, $email)  = CRM_Contact_BAO_Contact_Location::getEmailDetails($contactID);
+    $entities['contact'] = ['id' => $contactID, 'display_name' => $displayName, 'email' => $email];
+
+    $participantRecords = civicrm_api3('ParticipantPayment', 'get', [
+      'contribution_id' => $contributionID,
+      'api.Participant.get' => ['return' => 'event_id'],
+      'sequential' => 1,
+    ])['values'];
+    if (!empty($participantRecords)) {
+      $entities['event'] = civicrm_api3('Event', 'getsingle', ['id' => $participantRecords[0]['api.Participant.get']['values'][0]['event_id']]);
+    }
+
+    return $entities;
+  }
+
+  /**
+   * @param int $contributionID
+   *
+   * @return int
+   */
+  public static function getPaymentContactID($contributionID) {
+    $contribution = civicrm_api3('Contribution', 'getsingle', [
+      'id' => $contributionID ,
+      'return' => ['contact_id'],
+    ]);
+    return (int) $contribution['contact_id'];
+  }
+  /**
+   * @param array $entities
+   *   Related entities as an array keyed by the various entities.
+   *
+   * @return array
+   *   Values required for the notification
+   *   - contact_id
+   *   - template_variables
+   *     - event (DAO of event if relevant)
+   */
+  public static function getConfirmationTemplateParameters($entities) {
+    $templateVariables = [
+      'contactDisplayName' => $entities['contact']['display_name'],
+      'totalAmount' => $entities['payment']['total'],
+      'amountOwed' => $entities['payment']['balance'],
+      'paymentAmount' => $entities['payment']['total_amount'],
+      'event' => NULL,
+      'component' => 'contribution',
+    ];
+    if (!empty($entities['event'])) {
+      $templateVariables['component'] = 'event';
+      $templateVariables['event'] = $entities['event'];
+    }
+
+    return self::filterUntestedTemplateVariables($templateVariables);
+  }
+
+  /**
+   * Filter out any untested variables.
+   *
+   * This just serves to highlight if any variables are added without a unit test also being added.
+   *
+   * (if hit then add a unit test for the param & add to this array).
+   *
+   * @param array $params
+   *
+   * @return array
+   */
+  public static function filterUntestedTemplateVariables($params) {
+    $testedTemplateVariables = [
+      'contactDisplayName',
+      'totalAmount',
+      'amountOwed',
+      'paymentAmount',
+      'event',
+      'component',
+    ];
+    // Need to do these before switching the form over...
+    $todoParams = [
+      'isRefund',
+      'totalPaid',
+      'refundAmount',
+      'paymentsComplete',
+      'receive_date',
+      'paidBy',
+      'checkNumber',
+      'contributeMode',
+      'isAmountzero',
+      'billingName',
+      'address',
+      'credit_card_type',
+      'credit_card_number',
+      'credit_card_exp_date',
+      'isShowLocation',
+      'location',
+      'eventEmail',
+      '$event.participant_role',
+    ];
+    $filteredParams = [];
+    foreach ($testedTemplateVariables as $templateVariable) {
+      // This will cause an a-notice if any are NOT set - by design. Ensuring
+      // they are set prevents leakage.
+      $filteredParams[$templateVariable] = $params[$templateVariable];
+    }
+    return $filteredParams;
+  }
+
 }
diff --git a/api/v3/Payment.php b/api/v3/Payment.php
index 355ea7ad50c5..a4292a5b6b71 100644
--- a/api/v3/Payment.php
+++ b/api/v3/Payment.php
@@ -235,3 +235,49 @@ function _civicrm_api3_payment_cancel_spec(&$params) {
     ),
   );
 }
+
+/**
+ * Send a payment confirmation.
+ *
+ * @param array $params
+ *   Input parameters.
+ *
+ * @return array
+ * @throws Exception
+ */
+function civicrm_api3_payment_sendconfirmation($params) {
+  $allowedParams = [
+    'receipt_from_email',
+    'receipt_from_name',
+    'cc_receipt',
+    'bcc_receipt',
+    'receipt_text',
+    'id',
+  ];
+  $input = array_intersect_key($params, array_flip($allowedParams));
+  // use either the contribution or membership receipt, based on whether it’s a membership-related contrib or not
+  $result = CRM_Financial_BAO_Payment::sendConfirmation($input);
+  return civicrm_api3_create_success([
+    $params['id'] => [
+      'is_sent' => $result[0],
+      'subject' => $result[1],
+      'message_txt' => $result[2],
+      'message_html' => $result[3],
+  ]]);
+}
+
+/**
+ * Adjust Metadata for sendconfirmation action.
+ *
+ * The metadata is used for setting defaults, documentation & validation.
+ *
+ * @param array $params
+ *   Array of parameters determined by getfields.
+ */
+function _civicrm_api3_payment_sendconfirmation_spec(&$params) {
+  $params['id'] = array(
+    'api.required' => 1,
+    'title' => ts('Payment ID'),
+    'type' => CRM_Utils_Type::T_INT,
+  );
+}
diff --git a/tests/phpunit/api/v3/PaymentTest.php b/tests/phpunit/api/v3/PaymentTest.php
index 85a3786745ff..5585a58f6b82 100644
--- a/tests/phpunit/api/v3/PaymentTest.php
+++ b/tests/phpunit/api/v3/PaymentTest.php
@@ -104,6 +104,39 @@ public function testGetPayment() {
     ));
   }
 
+  /**
+   * Test email receipt for partial payment.
+   */
+  public function testPaymentEmailReceipt() {
+    $mut = new CiviMailUtils($this);
+    list($lineItems, $contribution) = $this->createParticipantWithContribution();
+    $params = array(
+      'contribution_id' => $contribution['id'],
+      'total_amount' => 50,
+    );
+    $payment = $this->callAPISuccess('payment', 'create', $params);
+    $this->checkPaymentResult($payment, [
+      $payment['id'] => [
+        'from_financial_account_id' => 7,
+        'to_financial_account_id' => 6,
+        'total_amount' => 50,
+        'status_id' => 1,
+        'is_payment' => 1,
+      ],
+    ]);
+
+    $this->callAPISuccess('Payment', 'sendconfirmation', ['id' => $payment['id']]);
+    $mut->assertSubjects(['Payment Receipt - Annual CiviCRM meet']);
+    $mut->checkMailLog(array(
+      'Dear Mr. Anthony Anderson II',
+      'Total Fees: $ 300.00',
+      'This Payment Amount: $ 50.00',
+      'Balance Owed: $ 100.00', //150 was paid in the 1st payment.
+      'Event Information and Location',
+    ));
+    $mut->stop();
+  }
+
   /**
    * Test create payment api with no line item in params
    */