diff --git a/src/contentScripts/communityConsole/workflows/actionRunners/readState.js b/src/contentScripts/communityConsole/workflows/actionRunners/readState.js
new file mode 100644
index 0000000..73d9a4f
--- /dev/null
+++ b/src/contentScripts/communityConsole/workflows/actionRunners/readState.js
@@ -0,0 +1,21 @@
+import {CCApi} from '../../../../common/api.js';
+import {getAuthUser} from '../../../../common/communityConsoleUtils.js';
+
+export default class ReadStateRunner {
+  execute(readState, thread) {
+    // Although this should in theory be the last message ID, it seems like
+    // setting 0 marks the entire thread as read anyways.
+    const lastMessageId = readState ? '0' : '-1';
+
+    return CCApi(
+        'SetUserReadStateBulk', {
+          // bulkItem:
+          1: [{
+            1: thread.forumId,
+            2: thread.threadId,
+            3: lastMessageId,
+          }],
+        },
+        /* authenticated = */ true, getAuthUser());
+  }
+}