diff --git a/CRM/Contribute/BAO/Contribution.php b/CRM/Contribute/BAO/Contribution.php
index 791ebe27a5b0..5e884b930ea9 100644
--- a/CRM/Contribute/BAO/Contribution.php
+++ b/CRM/Contribute/BAO/Contribution.php
@@ -2611,9 +2611,9 @@ protected static function repeatTransaction(&$contribution, &$input, $contributi
         ])
       );
       $input['line_item'] = $contributionParams['line_item'] = $templateContribution['line_item'];
-
       $contributionParams['status_id'] = 'Pending';
-      if (isset($contributionParams['financial_type_id'])) {
+
+      if (isset($contributionParams['financial_type_id']) && count($input['line_item']) === 1) {
         // Give precedence to passed in type.
         $contribution->financial_type_id = $contributionParams['financial_type_id'];
       }
@@ -4440,10 +4440,8 @@ public static function completeOrder($input, &$ids, $objects, $transaction = NUL
       'contribution_status_id',
       'card_type_id',
       'pan_truncation',
+      'financial_type_id',
     ];
-    if (self::isSingleLineItem($primaryContributionID)) {
-      $inputContributionWhiteList[] = 'financial_type_id';
-    }
 
     $participant = $objects['participant'] ?? NULL;
     $recurContrib = $objects['contributionRecur'] ?? NULL;
@@ -4487,6 +4485,12 @@ public static function completeOrder($input, &$ids, $objects, $transaction = NUL
     $changeDate = CRM_Utils_Array::value('trxn_date', $input, date('YmdHis'));
 
     self::repeatTransaction($contribution, $input, $contributionParams, $paymentProcessorId);
+    // @todo this line only exists because after we save the contribution in repeatTransaction
+    // with the correct params we resave it shortly after this with ahem params.
+    // if we stop doing that per
+    // https://github.com/civicrm/civicrm-core/pull/17972
+    // this line can go. Test cover in testRepeatTransactionPassedInFinancialTypeTwoLineItems
+    // and testRepeatTransactionPassedInFinancialType
     $contributionParams['financial_type_id'] = $contribution->financial_type_id;
 
     $values = [];
@@ -4533,6 +4537,7 @@ public static function completeOrder($input, &$ids, $objects, $transaction = NUL
 
     // CRM-19309 - if you update the contribution here with financial_type_id it can/will mess with $lineItem
     // unsetting it here does NOT cause any other contribution test to fail!
+    // this will no longer be required once we stop setting it above/ stop double saving.
     unset($contributionParams['financial_type_id']);
     $contributionResult = civicrm_api3('Contribution', 'create', $contributionParams);
 
diff --git a/CRM/Contribute/BAO/ContributionRecur.php b/CRM/Contribute/BAO/ContributionRecur.php
index 72d5d4eaf943..4bae1b03db1d 100644
--- a/CRM/Contribute/BAO/ContributionRecur.php
+++ b/CRM/Contribute/BAO/ContributionRecur.php
@@ -442,8 +442,11 @@ public static function getTemplateContribution($id, $overrides = []) {
     }
     if ($templateContributions->count()) {
       $templateContribution = $templateContributions->first();
-      $result = array_merge($templateContribution, $overrides);
       $lineItems = CRM_Price_BAO_LineItem::getLineItemsByContributionID($templateContribution['id']);
+      if (count($lineItems) > 1 && isset($overrides['financial_type_id'])) {
+        unset($overrides['financial_type_id']);
+      }
+      $result = array_merge($templateContribution, $overrides);
       $result['line_item'] = self::reformatLineItemsForRepeatContribution($result['total_amount'], $result['financial_type_id'], $lineItems, (array) $templateContribution);
       return $result;
     }
diff --git a/tests/phpunit/api/v3/ContributionTest.php b/tests/phpunit/api/v3/ContributionTest.php
index 70e9db324823..8de1b2272f97 100644
--- a/tests/phpunit/api/v3/ContributionTest.php
+++ b/tests/phpunit/api/v3/ContributionTest.php
@@ -2684,7 +2684,10 @@ public function testRepeatTransactionAlteredAmount() {
   }
 
   /**
-   * CRM-17718 test appropriate action if financial type has changed for single line items.
+   * Test financial_type_id override behaviour with a single line item.
+   *
+   * CRM-17718 a passed in financial_type_id is allowed to override the original contribution where there
+   * is only one line item.
    */
   public function testRepeatTransactionPassedInFinancialType() {
     $originalContribution = $this->setUpRecurringContribution();
@@ -2711,7 +2714,7 @@ public function testRepeatTransactionPassedInFinancialType() {
       ],
     ];
 
-    $this->callAPISuccessGetSingle('contribution', [
+    $this->callAPISuccessGetSingle('Contribution', [
       'total_amount' => 100,
       'financial_type_id' => 2,
     ]);
@@ -2734,6 +2737,37 @@ public function testRepeatTransactionPassedInFinancialType() {
     $this->assertEquals($expectedLineItem, $lineItem2['values'][0]);
   }
 
+  /**
+   * Test financial_type_id override behaviour with a single line item.
+   *
+   * CRM-17718 a passed in financial_type_id is not allowed to override the original contribution where there
+   * is more than one line item.
+   */
+  public function testRepeatTransactionPassedInFinancialTypeTwoLineItems() {
+    $this->_params = $this->getParticipantOrderParams();
+    $originalContribution = $this->setUpRecurringContribution();
+
+    $this->callAPISuccess('Contribution', 'repeattransaction', [
+      'original_contribution_id' => $originalContribution['id'],
+      'contribution_status_id' => 'Completed',
+      'trxn_id' => 'repeat',
+      'financial_type_id' => 2,
+    ]);
+
+    // Retrieve the new contribution and note the financial type passed in has been ignored.
+    $contribution = $this->callAPISuccessGetSingle('Contribution', [
+      'trxn_id' => 'repeat',
+    ]);
+    $this->assertEquals(4, $contribution['financial_type_id']);
+
+    $lineItems = $this->callAPISuccess('line_item', 'get', [
+      'entity_id' => $contribution['id'],
+    ])['values'];
+    foreach ($lineItems as $lineItem) {
+      $this->assertNotEquals(2, $lineItem['financial_type_id']);
+    }
+  }
+
   /**
    * CRM-17718 test appropriate action if financial type has changed for single line items.
    */
@@ -4064,6 +4098,7 @@ public function _deletedAddedPaymentInstrument() {
    *   Parameters to merge into the recur only.
    *
    * @return array|int
+   * @throws \CRM_Core_Exception
    */
   protected function setUpRecurringContribution($generalParams = [], $recurParams = []) {
     $contributionRecur = $this->callAPISuccess('contribution_recur', 'create', array_merge([
@@ -4077,12 +4112,14 @@ protected function setUpRecurringContribution($generalParams = [], $recurParams
       'frequency_unit' => 'month',
       'payment_processor_id' => $this->paymentProcessorID,
     ], $generalParams, $recurParams));
-    $originalContribution = $this->callAPISuccess('contribution', 'create', array_merge(
+    $contributionParams = array_merge(
       $this->_params,
       [
         'contribution_recur_id' => $contributionRecur['id'],
-      ], $generalParams)
-    );
+        'contribution_status_id' => 'Pending',
+      ], $generalParams);
+    $contributionParams['api.Payment.creaate'] = $contributionParams['total_amount'];
+    $originalContribution = $this->callAPISuccess('Order', 'create', $contributionParams);
     return $originalContribution;
   }