diff --git a/lib/firestore.js b/lib/firestore.js
index 78bbe4a..fb78942 100644
--- a/lib/firestore.js
+++ b/lib/firestore.js
@@ -1005,6 +1005,12 @@ async function updateNewsletter(newsletterID, newsletter) {
   return getNewsletter(newsletterID)
 }
 
+async function addPromotionEmails(email) {
+  const promotionEmail = Object.assign({ email, from: 'life-etiquette-park' })
+  let ref = bunkoFS.collection('promotion-emails').doc()
+  await ref.set(promotionEmail)
+}
+
 export const bunko = {
   countDocs,
   getDocs,
@@ -1050,7 +1056,8 @@ export const bunko = {
   getNewsletters,
   getNewsletter,
   addNewsletter,
-  updateNewsletter
+  updateNewsletter,
+  addPromotionEmails
 }
 
 async function getAncms() {