diff --git a/lib/actions/message-actions.js b/lib/actions/message-actions.js
--- a/lib/actions/message-actions.js
+++ b/lib/actions/message-actions.js
@@ -29,7 +29,10 @@
   RawMessageInfo,
   MessageTruncationStatuses,
 } from '../types/message-types.js';
-import { defaultNumberPerThread } from '../types/message-types.js';
+import {
+  defaultNumberPerThread,
+  messageTruncationStatus,
+} from '../types/message-types.js';
 import type { MediaMessageServerDBContent } from '../types/messages/media.js';
 import type { ThreadInfo } from '../types/minimally-encoded-thread-permissions-types.js';
 import { threadTypeIsThick } from '../types/thread-types-enum.js';
@@ -40,6 +43,7 @@
 import { getConfig } from '../utils/config.js';
 import { translateClientDBMessageInfoToRawMessageInfo } from '../utils/message-ops-utils.js';
 import { useDispatchActionPromise } from '../utils/redux-promise-utils.js';
+import { useSelector } from '../utils/redux-utils.js';
 
 const fetchMessagesBeforeCursorActionTypes = Object.freeze({
   started: 'FETCH_MESSAGES_BEFORE_CURSOR_STARTED',
@@ -545,6 +549,29 @@
   return useKeyserverCall(toggleMessagePin);
 }
 
+async function fetchThickThreadMessages(
+  threadID: string,
+  limit: number,
+  offset: number,
+): Promise<FetchMessageInfosPayload> {
+  const { sqliteAPI } = getConfig();
+  const dbMessages = await sqliteAPI.fetchMessages(threadID, limit + 1, offset);
+  const isFetchExhaustive = dbMessages.length !== limit + 1;
+  const messagesToReturn = isFetchExhaustive
+    ? dbMessages
+    : dbMessages.slice(0, -1);
+  const messages = messagesToReturn.map(
+    translateClientDBMessageInfoToRawMessageInfo,
+  );
+  return {
+    threadID,
+    rawMessageInfos: messages,
+    truncationStatus: isFetchExhaustive
+      ? messageTruncationStatus.EXHAUSTIVE
+      : messageTruncationStatus.UNCHANGED,
+  };
+}
+
 function useFetchMessages(threadInfo: ThreadInfo): () => Promise<void> {
   const oldestMessageServerID = useOldestMessageServerID(threadInfo.id);
   const callFetchMessagesBeforeCursor = useFetchMessagesBeforeCursor();
@@ -556,9 +583,31 @@
     registerFetchKey(fetchMostRecentMessagesActionTypes);
   }, []);
 
+  const threadID = threadInfo.id;
+  const messageIDs = useSelector(
+    state => state.messageStore.threads[threadID].messageIDs,
+  );
+  const numberOfFetchedMessages = React.useRef(messageIDs?.length ?? 0);
+
+  React.useEffect(() => {
+    numberOfFetchedMessages.current = 0;
+  }, [threadInfo.id]);
+
   return React.useCallback(async () => {
-    const threadID = threadInfo.id;
     if (threadTypeIsThick(threadInfo.type)) {
+      const promise = (async () => {
+        const fetchResult = await fetchThickThreadMessages(
+          threadID,
+          defaultNumberPerThread,
+          numberOfFetchedMessages.current,
+        );
+        numberOfFetchedMessages.current += fetchResult.rawMessageInfos.length;
+        return fetchResult;
+      })();
+      await dispatchActionPromise(
+        fetchMessagesBeforeCursorActionTypes,
+        promise,
+      );
       return;
     }
     if (oldestMessageServerID) {
@@ -580,7 +629,7 @@
     callFetchMostRecentMessages,
     dispatchActionPromise,
     oldestMessageServerID,
-    threadInfo.id,
+    threadID,
     threadInfo.type,
   ]);
 }
diff --git a/lib/reducers/message-reducer.js b/lib/reducers/message-reducer.js
--- a/lib/reducers/message-reducer.js
+++ b/lib/reducers/message-reducer.js
@@ -606,6 +606,26 @@
     updatedThreads[threadID] = threads[threadID];
   }
 
+  const dbOps = [
+    ...newMessageOps,
+    {
+      type: 'replace_threads',
+      payload: {
+        threads: Object.fromEntries(
+          Object.entries(updatedThreads).map(([threadID, thread]) => [
+            threadID,
+            threadInfos[threadID].thick
+              ? {
+                  ...thread,
+                  startReached:
+                    thread.messageIDs.length < defaultNumberPerThread,
+                }
+              : thread,
+          ]),
+        ),
+      },
+    },
+  ];
   newMessageOps.push({
     type: 'replace_threads',
     payload: {
@@ -640,10 +660,7 @@
   };
 
   return {
-    messageStoreOperations: [
-      ...updateWithLatestThreadInfosOps,
-      ...newMessageOps,
-    ],
+    messageStoreOperations: [...updateWithLatestThreadInfosOps, ...dbOps],
     messageStore,
   };
 }