diff --git a/src/app/features/common-settings/general/RoomUpgrade.tsx b/src/app/features/common-settings/general/RoomUpgrade.tsx
index 436d6445a..c3c89a589 100644
--- a/src/app/features/common-settings/general/RoomUpgrade.tsx
+++ b/src/app/features/common-settings/general/RoomUpgrade.tsx
@@ -40,6 +40,7 @@ import { creatorsSupported } from '../../../utils/matrix';
 import { useRoomCreators } from '../../../hooks/useRoomCreators';
 import { BreakWord } from '../../../styles/Text.css';
 import { useModalStyle } from '../../../hooks/useModalStyle';
+import { stateToCarry } from '../../../utils/roomUpgradeState';
 
 function RoomUpgradeDialog({ requestClose }: { requestClose: () => void }) {
   const mx = useMatrixClient();
@@ -63,10 +64,41 @@ function RoomUpgradeDialog({ requestClose }: { requestClose: () => void }) {
   const [upgradeState, upgrade] = useAsyncCallback(
     useCallback(
       async (version: string, newAdditionalCreators?: string[]) => {
-        await mx.http.authedRequest(Method.Post, `/rooms/${room.roomId}/upgrade`, undefined, {
-          new_version: version,
-          additional_creators: newAdditionalCreators,
-        });
+        // [Gitea #327] Synapse doesn't copy Lotus room state (voice limit, call
+        // policy, soundboard, retention, role tags, emoji packs) into the
+        // replacement room: read it first, re-create it after the upgrade.
+        const carried = stateToCarry(
+          Array.from(room.currentState.events.values()).flatMap((byKey) =>
+            Array.from(byKey.values()),
+          ),
+        );
+        const res = await mx.http.authedRequest<{ replacement_room?: string }>(
+          Method.Post,
+          `/rooms/${room.roomId}/upgrade`,
+          undefined,
+          {
+            new_version: version,
+            additional_creators: newAdditionalCreators,
+          },
+        );
+        const newRoomId = res?.replacement_room;
+        if (!newRoomId || carried.length === 0) return;
+        const results = await Promise.allSettled(
+          carried.map((st) =>
+            mx.http.authedRequest(
+              Method.Put,
+              `/rooms/${encodeURIComponent(newRoomId)}/state/${encodeURIComponent(st.type)}/${encodeURIComponent(st.stateKey)}`,
+              undefined,
+              st.content,
+            ),
+          ),
+        );
+        const failed = results.filter((r) => r.status === 'rejected').length;
+        if (failed > 0) {
+          throw new Error(
+            `Room upgraded, but ${failed} of ${carried.length} Lotus settings (voice limit, call policy, soundboard, retention…) could not be copied to the new room.`,
+          );
+        }
       },
       [mx, room],
     ),
diff --git a/src/app/utils/roomUpgradeState.test.ts b/src/app/utils/roomUpgradeState.test.ts
new file mode 100644
index 000000000..02e53cb16
--- /dev/null
+++ b/src/app/utils/roomUpgradeState.test.ts
@@ -0,0 +1,35 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { isCarriedStateType, stateToCarry } from './roomUpgradeState';
+
+const ev = (type: string, content: Record<string, unknown>, stateKey = '') => ({
+  getType: () => type,
+  getStateKey: () => stateKey,
+  getContent: () => content,
+});
+
+test('Lotus room state is carried; state Synapse already copies is not (#327)', () => {
+  assert.equal(isCarriedStateType('io.lotus.voice_limit'), true);
+  assert.equal(isCarriedStateType('io.lotus.room_quality'), true);
+  assert.equal(isCarriedStateType('io.lotus.soundboard'), true);
+  assert.equal(isCarriedStateType('m.room.retention'), true);
+  assert.equal(isCarriedStateType('in.cinny.room.power_level_tags'), true);
+  assert.equal(isCarriedStateType('im.ponies.room_emotes'), true);
+  assert.equal(isCarriedStateType('m.room.power_levels'), false);
+  assert.equal(isCarriedStateType('m.room.name'), false);
+  assert.equal(isCarriedStateType('m.room.member'), false);
+});
+
+test('stateToCarry keeps state keys and skips emptied events', () => {
+  const out = stateToCarry([
+    ev('io.lotus.voice_limit', { max_users: 5 }),
+    ev('io.lotus.soundboard', { clips: [1] }, 'pack-a'),
+    ev('io.lotus.room_quality', {}),
+    ev('m.room.name', { name: 'x' }),
+    ev('m.room.retention', { max_lifetime: 604800000 }),
+  ]);
+  assert.deepEqual(
+    out.map((s) => `${s.type}|${s.stateKey}`),
+    ['io.lotus.voice_limit|', 'io.lotus.soundboard|pack-a', 'm.room.retention|'],
+  );
+});
diff --git a/src/app/utils/roomUpgradeState.ts b/src/app/utils/roomUpgradeState.ts
new file mode 100644
index 000000000..ca6036bd4
--- /dev/null
+++ b/src/app/utils/roomUpgradeState.ts
@@ -0,0 +1,36 @@
+/**
+ * [Gitea #327] Room state Synapse does NOT copy into the replacement room on
+ * `POST /rooms/{id}/upgrade` (it carries only power levels, join rules,
+ * name/topic/avatar, history visibility, guest access, encryption, server ACL
+ * and space parent/child). Lotus keeps call policy, voice limits, soundboard,
+ * message retention, role tags and room emoji packs in state, so an upgrade
+ * silently dropped all of them.
+ */
+const CARRIED_TYPES = new Set([
+  'm.room.retention',
+  'in.cinny.room.power_level_tags',
+  'im.ponies.room_emotes',
+]);
+const CARRIED_PREFIXES = ['io.lotus.'];
+
+export type StateToCarry = { type: string; stateKey: string; content: Record<string, unknown> };
+
+export const isCarriedStateType = (type: string): boolean =>
+  CARRIED_TYPES.has(type) || CARRIED_PREFIXES.some((p) => type.startsWith(p));
+
+/** The state events to re-create in the replacement room (non-empty content only). */
+export const stateToCarry = (
+  events: Array<{
+    getType: () => string;
+    getStateKey: () => string | undefined;
+    getContent: () => Record<string, unknown>;
+  }>,
+): StateToCarry[] =>
+  events
+    .filter((ev) => isCarriedStateType(ev.getType()))
+    .map((ev) => ({
+      type: ev.getType(),
+      stateKey: ev.getStateKey() ?? '',
+      content: ev.getContent(),
+    }))
+    .filter((s) => s.content && Object.keys(s.content).length > 0);