diff --git a/src/blocks/donate/class-wp-rest-newspack-donate-controller.php b/src/blocks/donate/class-wp-rest-newspack-donate-controller.php
index de3f9a175..49eef67bf 100644
--- a/src/blocks/donate/class-wp-rest-newspack-donate-controller.php
+++ b/src/blocks/donate/class-wp-rest-newspack-donate-controller.php
@@ -124,9 +124,15 @@ public function api_process_donation( $request ) {
 			}
 		}
 
+		$referer = $request->get_param( '_wp_http_referer' );
+		if ( ! $referer ) {
+			$referer = \wp_get_referer();
+		}
+
 		$payment_metadata = [
-			'referer' => \wp_get_referer(),
+			'referer' => $referer,
 		];
+
 		if ( class_exists( 'Newspack\NRH' ) && method_exists( 'Newspack\NRH', 'get_nrh_config' ) ) {
 			$nrh_config = \Newspack\NRH::get_nrh_config();
 			if ( isset( $nrh_config['nrh_salesforce_campaign_id'] ) ) {
@@ -134,6 +140,10 @@ public function api_process_donation( $request ) {
 			}
 		}
 
+		if ( ! empty( $request->get_param( 'newspack_popup_id' ) ) ) {
+			$payment_metadata['newspack_popup_id'] = $request->get_param( 'newspack_popup_id' );
+		}
+
 		$frequency = $request->get_param( 'frequency' );
 		$full_name = $request->get_param( 'full_name' );
 		$origin    = $request->get_param( 'origin' );
diff --git a/src/blocks/donate/frontend/class-newspack-blocks-donate-renderer-base.php b/src/blocks/donate/frontend/class-newspack-blocks-donate-renderer-base.php
index 9ebb827c9..9cd07f0fa 100644
--- a/src/blocks/donate/frontend/class-newspack-blocks-donate-renderer-base.php
+++ b/src/blocks/donate/frontend/class-newspack-blocks-donate-renderer-base.php
@@ -300,6 +300,11 @@ protected static function render_streamlined_payment_ui( $attributes ) {
 	 */
 	protected static function render_donate_form_input() {
 		ob_start();
+		/**
+		 * Action to add custom fields before the form fields of the donation block.
+		 */
+		do_action( 'newspack_blocks_donate_before_form_fields' );
+		wp_referer_field();
 		?>
 			<input type='hidden' name='newspack_donate' value='1' />
 		<?php
diff --git a/src/blocks/donate/streamlined/index.ts b/src/blocks/donate/streamlined/index.ts
index 5e63760fa..77fdb06d9 100644
--- a/src/blocks/donate/streamlined/index.ts
+++ b/src/blocks/donate/streamlined/index.ts
@@ -136,6 +136,8 @@ export const processStreamlinedElements = ( parentElement = document ) =>
 				full_name: formValues.full_name,
 				frequency: formValues.donation_frequency,
 				newsletter_opt_in: Boolean( formValues.newsletter_opt_in ),
+				newspack_popup_id: formValues.newspack_popup_id,
+				_wp_http_referer: formValues._wp_http_referer,
 				clientId: formValues.cid,
 				origin,
 				additional_fields: additionalFields,
diff --git a/src/blocks/donate/types.ts b/src/blocks/donate/types.ts
index 144e476d8..01493f87c 100644
--- a/src/blocks/donate/types.ts
+++ b/src/blocks/donate/types.ts
@@ -20,6 +20,8 @@ export type DonationFormValues = {
 	cid?: string;
 	agree_to_pay_fees?: string;
 	newsletter_opt_in?: string;
+	newspack_popup_id?: string;
+	_wp_http_referer?: string;
 };
 
 export type DonationSettings = {