diff --git a/account/src/lib/couch-db.ts b/account/src/lib/couch-db.ts
index 830552d..ebc81f0 100644
--- a/account/src/lib/couch-db.ts
+++ b/account/src/lib/couch-db.ts
@@ -107,6 +107,12 @@ export async function updateLingdocsUser(uuid: T.UUID, toUpdate:
     couchDbPassword: T.UserDbPassword,
     upgradeToStudentRequest: undefined,
   } |
+  {
+    level: "basic",
+    wordlistDbName: undefined,
+    couchDbPassword: undefined,
+    upgradeToStudentRequest: undefined,
+  } |
   { upgradeToStudentRequest: "waiting" } | 
   { upgradeToStudentRequest: "denied" } |
   { tests: T.TestResult[] }
diff --git a/account/src/lib/user-utils.ts b/account/src/lib/user-utils.ts
index ab29664..8754cf7 100644
--- a/account/src/lib/user-utils.ts
+++ b/account/src/lib/user-utils.ts
@@ -3,6 +3,7 @@ import {
     insertLingdocsUser,
     addCouchDbAuthUser,
     updateLingdocsUser,
+    deleteCouchDbAuthUser,
 } from "../lib/couch-db";
 import {
     getHash,
@@ -71,6 +72,25 @@ export async function upgradeUser(userId: T.UUID): Promise<T.UpgradeUserResponse
     };
 }
 
+export async function downgradeUser(userId: T.UUID): Promise<T.DowngradeUserResponse> {
+    await deleteCouchDbAuthUser(userId);
+    const user = await updateLingdocsUser(userId, {
+        level: "basic",
+        wordlistDbName: undefined,
+        couchDbPassword: undefined,
+        upgradeToStudentRequest: undefined,
+    });
+    if (user.email) {
+        // TODO
+        // sendAccountDowngradeMessage(user).catch(console.error);
+    }
+    return {
+        ok: true,
+        message: "user downgraded to basic",
+        user,
+    };
+}
+
 export async function denyUserUpgradeRequest(userId: T.UUID): Promise<void> {
     await updateLingdocsUser(userId, {
         upgradeToStudentRequest: "denied",
diff --git a/account/src/routers/payment-router.ts b/account/src/routers/payment-router.ts
index ac6146b..86d85f2 100644
--- a/account/src/routers/payment-router.ts
+++ b/account/src/routers/payment-router.ts
@@ -2,7 +2,7 @@ import express from "express";
 import * as T from "../../../website/src/types/account-types";
 import env from "../lib/env-vars";
 import Stripe from "stripe";
-import { upgradeUser } from "../lib/user-utils";
+import { downgradeUser, upgradeUser } from "../lib/user-utils";
 
 const stripe = new Stripe(env.stripeSecretKey, {
     apiVersion: "2022-08-01",
@@ -39,18 +39,20 @@ paymentRouter.post(
     let subscription: Stripe.Subscription;
     let status: Stripe.Subscription.Status;
     // Handle the event
+    const userId = event.data.object.subscription.metadata.userId as T.UUID;
     switch (event.type) {
       case 'customer.subscription.deleted':
         subscription = event.data.object;
         status = subscription.status;
         console.log(`Subscription status is ${status}.`);
+        console.log(`Downgrading user ${userId}.`);
+        await downgradeUser(userId);
         // Then define and call a method to handle the subscription deleted.
         // handleSubscriptionDeleted(subscriptionDeleted);
         break;
       case 'customer.subscription.created':
         subscription = event.data.object;
         status = subscription.status;
-        const userId = subscription.metadata.userId as T.UUID;
         console.log(`Upgrading user ${userId}.`);
         await upgradeUser(userId);
         // TODO: save subscription to db
diff --git a/website/src/types/account-types.ts b/website/src/types/account-types.ts
index afa420f..fb582b1 100644
--- a/website/src/types/account-types.ts
+++ b/website/src/types/account-types.ts
@@ -75,6 +75,12 @@ export type UpgradeUserResponse = {
     user: LingdocsUser,
 };
 
+export type DowngradeUserResponse = {
+    ok: true,
+    message: "user downgraded to basic",
+    user: LingdocsUser,
+};
+
 export type PostTestResultsBody = { tests: TestResult[] };
 export type PostTestResultsResponse = {
     ok: true,