diff --git a/lib/actions/entry-actions.js b/lib/actions/entry-actions.js
--- a/lib/actions/entry-actions.js
+++ b/lib/actions/entry-actions.js
@@ -5,7 +5,7 @@
   sortCalendarQueryPerKeyserver,
 } from '../keyserver-conn/keyserver-call-utils.js';
 import type { CallKeyserverEndpoint } from '../keyserver-conn/keyserver-conn-types.js';
-import { localIDPrefix } from '../shared/message-utils.js';
+import { getNextLocalID } from '../shared/message-utils.js';
 import type {
   RawEntryInfo,
   CalendarQuery,
@@ -127,13 +127,13 @@
 const createLocalEntryActionType = 'CREATE_LOCAL_ENTRY';
 function createLocalEntry(
   threadID: string,
-  localID: number,
   dateString: string,
   creatorID: string,
 ): RawEntryInfo {
   const date = dateFromString(dateString);
+  const localID = getNextLocalID();
   const newEntryInfo: RawEntryInfo = {
-    localID: `${localIDPrefix}${localID}`,
+    localID,
     threadID,
     text: '',
     year: date.getFullYear(),
diff --git a/lib/shared/message-utils.js b/lib/shared/message-utils.js
--- a/lib/shared/message-utils.js
+++ b/lib/shared/message-utils.js
@@ -4,6 +4,7 @@
 import _maxBy from 'lodash/fp/maxBy.js';
 import _orderBy from 'lodash/fp/orderBy.js';
 import * as React from 'react';
+import uuid from 'uuid';
 
 import { codeBlockRegex, type ParserRules } from './markdown.js';
 import type { CreationSideEffectsFunc } from './messages/message-spec.js';
@@ -654,8 +655,8 @@
   return ET`assigned ${affectedUsers} the "${roleName}" role`;
 }
 
-function useNextLocalID(): string {
-  const nextLocalID = useSelector(state => state.nextLocalID);
+function getNextLocalID(): string {
+  const nextLocalID = uuid.v4();
   return `${localIDPrefix}${nextLocalID}`;
 }
 
@@ -744,7 +745,7 @@
   getPinnedContentFromMessage,
   modifyItemForResultScreen,
   constructChangeRoleEntityText,
-  useNextLocalID,
+  getNextLocalID,
   isInvalidSidebarSource,
   isInvalidPinSource,
   isInvalidPinSourceForThread,
diff --git a/native/calendar/thread-picker-modal.react.js b/native/calendar/thread-picker-modal.react.js
--- a/native/calendar/thread-picker-modal.react.js
+++ b/native/calendar/thread-picker-modal.react.js
@@ -40,7 +40,6 @@
   const viewerID = useSelector(
     state => state.currentUserInfo && state.currentUserInfo.id,
   );
-  const nextLocalID = useSelector(state => state.nextLocalID);
   const dispatch = useDispatch();
 
   const rootNavigatorContext = React.useContext(RootNavigatorContext);
@@ -53,10 +52,10 @@
       rootNavigatorContext.setKeyboardHandlingEnabled(false);
       dispatch({
         type: createLocalEntryActionType,
-        payload: createLocalEntry(threadID, nextLocalID, dateString, viewerID),
+        payload: createLocalEntry(threadID, dateString, viewerID),
       });
     },
-    [rootNavigatorContext, dispatch, viewerID, nextLocalID, dateString],
+    [rootNavigatorContext, dispatch, viewerID, dateString],
   );
 
   React.useEffect(
diff --git a/native/chat/chat-input-bar.react.js b/native/chat/chat-input-bar.react.js
--- a/native/chat/chat-input-bar.react.js
+++ b/native/chat/chat-input-bar.react.js
@@ -53,7 +53,7 @@
   type MessagePreviewResult,
   trimMessage,
   useMessagePreview,
-  useNextLocalID,
+  getNextLocalID,
 } from 'lib/shared/message-utils.js';
 import SentencePrefixSearchIndex from 'lib/shared/sentence-prefix-search-index.js';
 import {
@@ -284,7 +284,6 @@
   +joinThreadLoadingStatus: LoadingStatus,
   +threadCreationInProgress: boolean,
   +calendarQuery: () => CalendarQuery,
-  +nextLocalID: string,
   +userInfos: UserInfos,
   +colors: Colors,
   +styles: $ReadOnly<typeof unboundStyles>,
@@ -973,7 +972,7 @@
       return;
     }
 
-    const localID = this.props.nextLocalID;
+    const localID = getNextLocalID();
     const creatorID = this.props.viewerID;
     invariant(creatorID, 'should have viewer ID in order to send a message');
     invariant(
@@ -1243,7 +1242,6 @@
       navContext,
     }),
   );
-  const nextLocalID = useNextLocalID();
   const userInfos = useSelector(state => state.userStore.userInfos);
 
   const styles = useStyles(unboundStyles);
@@ -1340,7 +1338,6 @@
       joinThreadLoadingStatus={joinThreadLoadingStatus}
       threadCreationInProgress={threadCreationInProgress}
       calendarQuery={calendarQuery}
-      nextLocalID={nextLocalID}
       userInfos={userInfos}
       colors={colors}
       styles={styles}
diff --git a/native/chat/inline-engagement.react.js b/native/chat/inline-engagement.react.js
--- a/native/chat/inline-engagement.react.js
+++ b/native/chat/inline-engagement.react.js
@@ -11,7 +11,6 @@
 
 import type { ReactionInfo } from 'lib/selectors/chat-selectors.js';
 import { getInlineEngagementSidebarText } from 'lib/shared/inline-engagement-utils.js';
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 import type { MessageInfo } from 'lib/types/message-types.js';
 import type { ThreadInfo } from 'lib/types/minimally-encoded-thread-permissions-types.js';
 
@@ -246,11 +245,8 @@
     repliesText,
   ]);
 
-  const localID = useNextLocalID();
-
   const sendReaction = useSendReaction(
     messageInfo.id,
-    localID,
     threadInfo.id,
     reactions,
   );
diff --git a/native/chat/multimedia-message-tooltip-button.react.js b/native/chat/multimedia-message-tooltip-button.react.js
--- a/native/chat/multimedia-message-tooltip-button.react.js
+++ b/native/chat/multimedia-message-tooltip-button.react.js
@@ -3,7 +3,6 @@
 import * as React from 'react';
 import Animated from 'react-native-reanimated';
 
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 import {
   useViewerAlreadySelectedMessageReactions,
   useCanCreateReactionFromMessage,
@@ -102,7 +101,6 @@
   );
 
   const { messageInfo, threadInfo, reactions } = item;
-  const localID = useNextLocalID();
 
   const canCreateReactionFromMessage = useCanCreateReactionFromMessage(
     threadInfo,
@@ -111,7 +109,6 @@
 
   const sendReaction = useSendReaction(
     messageInfo.id,
-    localID,
     threadInfo.id,
     reactions,
   );
diff --git a/native/chat/reaction-message-utils.js b/native/chat/reaction-message-utils.js
--- a/native/chat/reaction-message-utils.js
+++ b/native/chat/reaction-message-utils.js
@@ -8,6 +8,7 @@
   sendReactionMessageActionTypes,
 } from 'lib/actions/message-actions.js';
 import type { ReactionInfo } from 'lib/selectors/chat-selectors.js';
+import { getNextLocalID } from 'lib/shared/message-utils.js';
 import { messageTypes } from 'lib/types/message-types-enum.js';
 import type { RawReactionMessageInfo } from 'lib/types/messages/reaction.js';
 import { cloneError } from 'lib/utils/errors.js';
@@ -22,7 +23,6 @@
 
 function useSendReaction(
   messageID: ?string,
-  localID: string,
   threadID: string,
   reactions: ReactionInfo,
 ): (reaction: string) => mixed {
@@ -39,6 +39,8 @@
         return;
       }
 
+      const localID = getNextLocalID();
+
       invariant(viewerID, 'viewerID should be set');
 
       const viewerReacted = reactions[reaction]
@@ -102,7 +104,6 @@
       viewerID,
       reactions,
       threadID,
-      localID,
       dispatchActionPromise,
       callSendReactionMessage,
     ],
diff --git a/native/chat/robotext-message-tooltip-button.react.js b/native/chat/robotext-message-tooltip-button.react.js
--- a/native/chat/robotext-message-tooltip-button.react.js
+++ b/native/chat/robotext-message-tooltip-button.react.js
@@ -3,7 +3,6 @@
 import * as React from 'react';
 import Animated from 'react-native-reanimated';
 
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 import {
   useViewerAlreadySelectedMessageReactions,
   useCanCreateReactionFromMessage,
@@ -85,7 +84,6 @@
   }, [initialCoordinates, isOpeningSidebar, item, progress, windowWidth]);
 
   const { messageInfo, threadInfo, reactions } = item;
-  const localID = useNextLocalID();
 
   const canCreateReactionFromMessage = useCanCreateReactionFromMessage(
     threadInfo,
@@ -94,7 +92,6 @@
 
   const sendReaction = useSendReaction(
     messageInfo.id,
-    localID,
     threadInfo.id,
     reactions,
   );
diff --git a/native/chat/text-message-tooltip-button.react.js b/native/chat/text-message-tooltip-button.react.js
--- a/native/chat/text-message-tooltip-button.react.js
+++ b/native/chat/text-message-tooltip-button.react.js
@@ -3,7 +3,6 @@
 import * as React from 'react';
 import Animated from 'react-native-reanimated';
 
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 import {
   useViewerAlreadySelectedMessageReactions,
   useCanCreateReactionFromMessage,
@@ -99,7 +98,6 @@
   }, [initialCoordinates, isOpeningSidebar, item, progress, windowWidth]);
 
   const { messageInfo, threadInfo, reactions } = item;
-  const localID = useNextLocalID();
 
   const canCreateReactionFromMessage = useCanCreateReactionFromMessage(
     threadInfo,
@@ -108,7 +106,6 @@
 
   const sendReaction = useSendReaction(
     messageInfo.id,
-    localID,
     threadInfo.id,
     reactions,
   );
diff --git a/native/input/input-state-container.react.js b/native/input/input-state-container.react.js
--- a/native/input/input-state-container.react.js
+++ b/native/input/input-state-container.react.js
@@ -42,7 +42,7 @@
 import {
   createMediaMessageInfo,
   useMessageCreationSideEffectsFunc,
-  useNextLocalID,
+  getNextLocalID,
 } from 'lib/shared/message-utils.js';
 import type { CreationSideEffectsFunc } from 'lib/shared/messages/message-spec.js';
 import {
@@ -137,7 +137,6 @@
 type Props = {
   ...BaseProps,
   +viewerID: ?string,
-  +nextLocalID: string,
   +messageStoreMessages: { +[id: string]: RawMessageInfo },
   +ongoingMessageCreation: boolean,
   +hasWiFi: boolean,
@@ -612,7 +611,7 @@
     threadInfo: ThreadInfo,
   ) => {
     this.sendCallbacks.forEach(callback => callback());
-    const localMessageID = this.props.nextLocalID;
+    const localMessageID = getNextLocalID();
     void this.startThreadCreation(threadInfo);
 
     if (threadIsPendingSidebar(threadInfo.id)) {
@@ -1718,7 +1717,6 @@
     const viewerID = useSelector(
       state => state.currentUserInfo && state.currentUserInfo.id,
     );
-    const nextLocalID = useNextLocalID();
     const messageStoreMessages = useSelector(
       state => state.messageStore.messages,
     );
@@ -1747,7 +1745,6 @@
       <InputStateContainer
         {...props}
         viewerID={viewerID}
-        nextLocalID={nextLocalID}
         messageStoreMessages={messageStoreMessages}
         ongoingMessageCreation={ongoingMessageCreation}
         hasWiFi={hasWiFi}
diff --git a/web/calendar/day.react.js b/web/calendar/day.react.js
--- a/web/calendar/day.react.js
+++ b/web/calendar/day.react.js
@@ -41,7 +41,6 @@
   +onScreenThreadInfos: $ReadOnlyArray<ThreadInfo>,
   +viewerID: ?string,
   +loggedIn: boolean,
-  +nextLocalID: number,
   +dispatch: Dispatch,
   +pushModal: PushModal,
   +popModal: () => void,
@@ -200,12 +199,7 @@
     invariant(viewerID, 'should have viewerID in order to create thread');
     this.props.dispatch({
       type: createLocalEntryActionType,
-      payload: createLocalEntry(
-        threadID,
-        this.props.nextLocalID,
-        this.props.dayString,
-        viewerID,
-      ),
+      payload: createLocalEntry(threadID, this.props.dayString, viewerID),
     });
   };
 
@@ -236,7 +230,6 @@
       state =>
         !!(state.currentUserInfo && !state.currentUserInfo.anonymous && true),
     );
-    const nextLocalID = useSelector(state => state.nextLocalID);
     const dispatch = useDispatch();
     const { pushModal, popModal } = useModalContext();
 
@@ -246,7 +239,6 @@
         onScreenThreadInfos={onScreenThreadInfos}
         viewerID={viewerID}
         loggedIn={loggedIn}
-        nextLocalID={nextLocalID}
         dispatch={dispatch}
         pushModal={pushModal}
         popModal={popModal}
diff --git a/web/chat/chat-input-bar.react.js b/web/chat/chat-input-bar.react.js
--- a/web/chat/chat-input-bar.react.js
+++ b/web/chat/chat-input-bar.react.js
@@ -24,7 +24,7 @@
   useMentionTypeaheadUserSuggestions,
   useUserMentionsCandidates,
 } from 'lib/shared/mention-utils.js';
-import { localIDPrefix, trimMessage } from 'lib/shared/message-utils.js';
+import { trimMessage, getNextLocalID } from 'lib/shared/message-utils.js';
 import {
   checkIfDefaultMembersAreVoiced,
   threadActualMembers,
@@ -75,7 +75,6 @@
   +joinThreadLoadingStatus: LoadingStatus,
   +threadCreationInProgress: boolean,
   +calendarQuery: () => CalendarQuery,
-  +nextLocalID: number,
   +isThreadActive: boolean,
   +userInfos: UserInfos,
   +dispatchActionPromise: DispatchActionPromise,
@@ -480,25 +479,19 @@
   };
 
   send() {
-    let { nextLocalID } = this.props;
-
     const text = trimMessage(this.props.inputState.draft);
     if (text) {
-      this.dispatchTextMessageAction(text, nextLocalID);
-      nextLocalID++;
+      this.dispatchTextMessageAction(text);
     }
     if (this.props.inputState.pendingUploads.length > 0) {
-      this.props.inputState.createMultimediaMessage(
-        nextLocalID,
-        this.props.threadInfo,
-      );
+      this.props.inputState.createMultimediaMessage(this.props.threadInfo);
     }
   }
 
-  dispatchTextMessageAction(text: string, nextLocalID: number) {
+  dispatchTextMessageAction(text: string) {
     this.props.inputState.setDraft('');
 
-    const localID = `${localIDPrefix}${nextLocalID}`;
+    const localID = getNextLocalID();
     const creatorID = this.props.viewerID;
     invariant(creatorID, 'should have viewer ID in order to send a message');
 
@@ -572,7 +565,6 @@
     const viewerID = useSelector(
       state => state.currentUserInfo && state.currentUserInfo.id,
     );
-    const nextLocalID = useSelector(state => state.nextLocalID);
     const isThreadActive = useSelector(
       state => props.threadInfo.id === state.navInfo.activeChatThreadID,
     );
@@ -671,7 +663,6 @@
         joinThreadLoadingStatus={joinThreadLoadingStatus}
         threadCreationInProgress={threadCreationInProgress}
         calendarQuery={calendarQuery}
-        nextLocalID={nextLocalID}
         isThreadActive={isThreadActive}
         userInfos={userInfos}
         dispatchActionPromise={dispatchActionPromise}
diff --git a/web/chat/reaction-message-utils.js b/web/chat/reaction-message-utils.js
--- a/web/chat/reaction-message-utils.js
+++ b/web/chat/reaction-message-utils.js
@@ -9,6 +9,7 @@
 } from 'lib/actions/message-actions.js';
 import { useModalContext } from 'lib/components/modal-provider.react.js';
 import type { ReactionInfo } from 'lib/selectors/chat-selectors';
+import { getNextLocalID } from 'lib/shared/message-utils.js';
 import { messageTypes } from 'lib/types/message-types-enum.js';
 import type { RawReactionMessageInfo } from 'lib/types/messages/reaction.js';
 import type { CallSingleKeyserverEndpointResultInfoInterface } from 'lib/utils/call-single-keyserver-endpoint.js';
@@ -25,7 +26,6 @@
 
 function useSendReaction(
   messageID: ?string,
-  localID: string,
   threadID: string,
   reactions: ReactionInfo,
 ): (reaction: string) => mixed {
@@ -44,6 +44,8 @@
         return;
       }
 
+      const localID = getNextLocalID();
+
       invariant(viewerID, 'viewerID should be set');
 
       const viewerReacted = reactions[reaction]
@@ -108,7 +110,6 @@
       viewerID,
       reactions,
       threadID,
-      localID,
       dispatchActionPromise,
       callSendReactionMessage,
       pushModal,
diff --git a/web/chat/reaction-pill.react.js b/web/chat/reaction-pill.react.js
--- a/web/chat/reaction-pill.react.js
+++ b/web/chat/reaction-pill.react.js
@@ -4,7 +4,6 @@
 import * as React from 'react';
 
 import type { ReactionInfo } from 'lib/selectors/chat-selectors.js';
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 
 import { useSendReaction } from './reaction-message-utils.js';
 import css from './reaction-pill.css';
@@ -26,8 +25,7 @@
 function ReactionPill(props: Props): React.Node {
   const { reaction, messageID, threadID, reactions } = props;
 
-  const localID = useNextLocalID();
-  const sendReaction = useSendReaction(messageID, localID, threadID, reactions);
+  const sendReaction = useSendReaction(messageID, threadID, reactions);
 
   const onClickReaction = React.useCallback(
     (event: SyntheticEvent<HTMLElement>) => {
diff --git a/web/input/input-state-container.react.js b/web/input/input-state-container.react.js
--- a/web/input/input-state-container.react.js
+++ b/web/input/input-state-container.react.js
@@ -47,6 +47,7 @@
   createMediaMessageInfo,
   localIDPrefix,
   useMessageCreationSideEffectsFunc,
+  getNextLocalID,
 } from 'lib/shared/message-utils.js';
 import type { CreationSideEffectsFunc } from 'lib/shared/messages/message-spec.js';
 import {
@@ -642,10 +643,8 @@
               parentThreadInfo: ?ThreadInfo,
             ) =>
               this.sendTextMessage(messageInfo, threadInfo, parentThreadInfo),
-            createMultimediaMessage: (
-              localID: number,
-              threadInfo: ThreadInfo,
-            ) => this.createMultimediaMessage(localID, threadInfo),
+            createMultimediaMessage: (threadInfo: ThreadInfo) =>
+              this.createMultimediaMessage(threadInfo),
             setDraft: (newDraft: string) => this.setDraft(threadID, newDraft),
             setTextCursorPosition: (newPosition: number) =>
               this.setTextCursorPosition(threadID, newPosition),
@@ -1395,10 +1394,10 @@
 
   // Creates a MultimediaMessage from the unassigned pending uploads,
   // if there are any
-  createMultimediaMessage(localID: number, threadInfo: ThreadInfo) {
+  createMultimediaMessage(threadInfo: ThreadInfo) {
     this.props.sendCallbacks.forEach(callback => callback());
 
-    const localMessageID = `${localIDPrefix}${localID}`;
+    const localMessageID = getNextLocalID();
     void this.startThreadCreation(threadInfo);
 
     if (threadIsPendingSidebar(threadInfo.id)) {
diff --git a/web/input/input-state.js b/web/input/input-state.js
--- a/web/input/input-state.js
+++ b/web/input/input-state.js
@@ -72,7 +72,7 @@
     threadInfo: ThreadInfo,
     parentThreadInfo: ?ThreadInfo,
   ) => mixed,
-  +createMultimediaMessage: (localID: number, threadInfo: ThreadInfo) => void,
+  +createMultimediaMessage: (threadInfo: ThreadInfo) => void,
   +setDraft: (draft: string) => void,
   +setTextCursorPosition: (newPosition: number) => void,
   +messageHasUploadFailure: (localMessageID: string) => boolean,
diff --git a/web/tooltips/message-tooltip.react.js b/web/tooltips/message-tooltip.react.js
--- a/web/tooltips/message-tooltip.react.js
+++ b/web/tooltips/message-tooltip.react.js
@@ -6,7 +6,6 @@
 import * as React from 'react';
 
 import type { ChatMessageInfoItem } from 'lib/selectors/chat-selectors.js';
-import { useNextLocalID } from 'lib/shared/message-utils.js';
 import type { ThreadInfo } from 'lib/types/minimally-encoded-thread-permissions-types.js';
 
 import css from './message-tooltip.css';
@@ -170,11 +169,8 @@
     };
   }, [emojiKeyboardPosition]);
 
-  const localID = useNextLocalID();
-
   const sendReaction = useSendReaction(
     messageInfo.id,
-    localID,
     threadInfo.id,
     reactions,
   );