diff --git a/frontend/src/pages/LocationMapManager.jsx b/frontend/src/pages/LocationMapManager.jsx
index c0dfcfc..ffd67ce 100644
--- a/frontend/src/pages/LocationMapManager.jsx
+++ b/frontend/src/pages/LocationMapManager.jsx
@@ -1,4 +1,4 @@
-import { useCallback, useContext, useEffect, useRef, useState } from "react";
+import { useCallback, useContext, useEffect, useMemo, useRef, useState } from "react";
 import { useBeforeUnload, useLocation, useNavigate, useParams } from "react-router-dom";
 import {
   createBlankLocationMap,
@@ -38,6 +38,8 @@ import {
 } from "../lib/locationMapUtils";
 import "../styles/pages/LocationMapManager.css";
 
+const EMPTY_MAP_ITEMS = [];
+
 export default function LocationMapManager() {
   const { storeId, locationId } = useParams();
   const navigate = useNavigate();
@@ -77,16 +79,44 @@ export default function LocationMapManager() {
   const location = mapState?.location || stores.find((store) => String(store.id) === String(locationId));
   const canManage = Boolean(mapState?.can_manage ?? ["owner", "admin"].includes(activeHousehold?.role));
   const activeMap = mapForMode(mapState, mode, previewDraft);
-  const selectedObject = objects.find((object) => getObjectKey(object) === selectedObjectKey) || null;
-  const selectedZoneItems = selectedObject?.zone_id
-    ? itemsForZone(mapState?.items || [], selectedObject.zone_id, filters, username)
-    : [];
-  const visibleUnmappedItems = unmappedItems(mapState?.items || [], filters, username);
-  const visibleAssignedItemCount = (mapState?.items || []).filter((item) => (
-    item.zone_id && itemMatchesMapFilters(item, filters, username)
-  )).length;
-  const unmappedItemCount = (mapState?.items || []).filter((item) => !item.zone_id).length;
-  const hiddenAreaCount = objects.filter((object) => object.visible === false).length;
+  const mapItems = mapState?.items || EMPTY_MAP_ITEMS;
+  const selectedObject = useMemo(
+    () => objects.find((object) => getObjectKey(object) === selectedObjectKey) || null,
+    [objects, selectedObjectKey]
+  );
+  const selectedZoneItems = useMemo(
+    () => selectedObject?.zone_id
+      ? itemsForZone(mapItems, selectedObject.zone_id, filters, username)
+      : EMPTY_MAP_ITEMS,
+    [filters, mapItems, selectedObject?.zone_id, username]
+  );
+  const visibleUnmappedItems = useMemo(
+    () => unmappedItems(mapItems, filters, username),
+    [filters, mapItems, username]
+  );
+  const { visibleAssignedItemCount, unmappedItemCount } = useMemo(() => {
+    let nextVisibleAssignedItemCount = 0;
+    let nextUnmappedItemCount = 0;
+
+    mapItems.forEach((item) => {
+      if (!item.zone_id) {
+        nextUnmappedItemCount += 1;
+        return;
+      }
+      if (itemMatchesMapFilters(item, filters, username)) {
+        nextVisibleAssignedItemCount += 1;
+      }
+    });
+
+    return {
+      visibleAssignedItemCount: nextVisibleAssignedItemCount,
+      unmappedItemCount: nextUnmappedItemCount,
+    };
+  }, [filters, mapItems, username]);
+  const hiddenAreaCount = useMemo(
+    () => objects.filter((object) => object.visible === false).length,
+    [objects]
+  );
   const shouldGuardLeave = canManage && hasUnsavedChanges;
 
   const mapSize = {
@@ -584,7 +614,7 @@ export default function LocationMapManager() {
               mapSize={mapSize}
               zoom={zoom}
               selectedObjectKey={selectedObjectKey}
-              mapItems={mapState?.items || []}
+              mapItems={mapItems}
               username={username}
               svgRef={svgRef}
               dragState={dragState}