diff --git a/spec/unit/matrix-client.spec.ts b/spec/unit/matrix-client.spec.ts
index fbe8c67d7e7..3fc8cd5274f 100644
--- a/spec/unit/matrix-client.spec.ts
+++ b/spec/unit/matrix-client.spec.ts
@@ -1297,4 +1297,37 @@ describe("MatrixClient", function() {
             expect(result!.aliases).toEqual(response.aliases);
         });
     });
+
+    describe("ignoring invites", () => {
+        it('stores ignored invites', async function() {
+            // Mockup account data storage.
+            const dataStore = new Map();
+            client.setAccountData = function(eventType, content) {
+                dataStore.set(eventType, content);
+                return Promise.resolve();
+            };
+            client.getAccountData = function(eventType) {
+                const data = dataStore.get(eventType);
+                return new MatrixEvent({
+                    content: data,
+                });
+            };
+
+            // Initially, the invite list should be empty but not `null`.
+            expect(await client.getIgnoredInvites()).toEqual({});
+
+            // Insert something, we should be able to recover it.
+            const SAMPLE = {
+                ignored_rooms: {
+                    "12345": {
+                        ts: Date.now(),
+                    },
+                },
+            };
+            await client.setIgnoredInvites(SAMPLE);
+
+            // Check that it was (mock)stored on the client.
+            expect(await client.getIgnoredInvites()).toEqual(SAMPLE);
+        });
+    });
 });
diff --git a/src/@types/event.ts b/src/@types/event.ts
index dac2770ade3..3a68f5378d3 100644
--- a/src/@types/event.ts
+++ b/src/@types/event.ts
@@ -81,6 +81,7 @@ export enum EventType {
     PushRules = "m.push_rules",
     Direct = "m.direct",
     IgnoredUserList = "m.ignored_user_list",
+    IgnoredInvites = "org.matrix.msc3840.ignored_invites",
 
     // to_device events
     RoomKey = "m.room_key",
diff --git a/src/client.ts b/src/client.ts
index 3058bca8658..b35162b11e5 100644
--- a/src/client.ts
+++ b/src/client.ts
@@ -3424,6 +3424,23 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
         return this.getIgnoredUsers().includes(userId);
     }
 
+    /**
+     * Gets the list of currently ignored invites.
+     */
+    public getIgnoredInvites(): IgnoredInvites {
+        const event = this.getAccountData(EventType.IgnoredInvites);
+        if (!event || !event.getContent()) return {};
+        return event.getContent();
+    }
+
+    /**
+     * Update the list of ignored invites.
+     * @param invites The new list of ignored invites.
+     */
+    public setIgnoredInvites(invites: IgnoredInvites): Promise<{}> {
+        return this.setAccountData(EventType.IgnoredInvites, invites);
+    }
+
     /**
      * Join a room. If you have already joined the room, this will no-op.
      * @param {string} roomIdOrAlias The room ID or room alias to join.
@@ -9320,3 +9337,35 @@ export class MatrixClient extends TypedEventEmitter<EmittedEvents, ClientEventHa
  * @event module:client~MatrixClient#"WellKnown.client"
  * @param {object} data The JSON object returned by the server
  */
+
+/**
+ * Metadata on ignored invites.
+ *
+ * This interface is expected to gain additional fields, all
+ * of them optional.
+ */
+export interface IgnoreInviteMetadata {
+    /**
+     * The instant the user decided to ignore this invite,
+     * as a Matrix timestamp.
+     */
+    readonly ts: number;
+
+     /**
+      * A human-readable reason for ignoring this invite.
+      */
+    readonly reason?: string;
+}
+
+/**
+ * Invites to ignore across all devices/sessions, as per MSC 3840.
+ *
+ * This interface is expected to gain additional fields, all of
+ * them optional.
+ */
+export interface IgnoredInvites {
+    /**
+     * A map of room ids => metadata for rooms the user does not wish to be invited to.
+     */
+    readonly ignored_rooms?: Record<string, IgnoreInviteMetadata>;
+}