diff --git a/src/common/state/user.js b/src/common/state/user.js
index 73f5da3..0aa9de9 100644
--- a/src/common/state/user.js
+++ b/src/common/state/user.js
@@ -77,14 +77,18 @@ const slice = createSlice({
   extraReducers: {
     [addMessage]: ({focus, unread}, {payload: {channel}}) => {
       if (focus !== channel) {
-        unread[channel] += 1;
+        unread[channel] = (unread[channel] || 0) + 1;
       }
     },
     [leave]: ({unread}, {payload: {channel}}) => {
       delete unread[channel];
     },
     [LOCATION_CHANGE]: (state, {payload: {location: {pathname}}}) => {
+      const {unread} = state;
       state.focus = pathname.match(/^\/chat\//) ? pathname.substr('/chat'.length) : '';
+      if (unread[state.focus]) {
+        delete unread[state.focus];
+      }
     },
   },
   /* eslint-enable no-param-reassign */