diff --git a/backend/src/lib/utilities-client.js b/backend/src/lib/utilities-client.js
index 3357c528..6edb09cb 100644
--- a/backend/src/lib/utilities-client.js
+++ b/backend/src/lib/utilities-client.js
@@ -3,13 +3,19 @@
 // routes/directors-forecast.js and routes/weekly-actual.js (X-API-Key header,
 // base URL + key from the app_settings table — set via Settings UI — with
 // env vars as a fallback, throw on non-2xx).
+//
+// The base URL points at the utilities app's nginx frontend (its backend
+// isn't published to the host), so requests must go through the
+// `/utilities/api/` proxy location — nginx strips that prefix and forwards
+// to the backend's bare `/api/internal/...` routes. Calling `/api/internal/...`
+// directly 404s since nginx has no location for un-prefixed paths.
 import { getSetting } from '../db.js'
 
 async function utilFetch(path) {
   const apiKey  = await getSetting('utilities_api_key') || process.env.UTILITIES_API_KEY
   const baseUrl = await getSetting('utilities_url') || process.env.UTILITIES_URL || 'http://10.10.10.127:3080'
   if (!apiKey) throw new Error('UTILITIES_API_KEY not configured')
-  const res = await fetch(`${baseUrl}${path}`, {
+  const res = await fetch(`${baseUrl}/utilities${path}`, {
     headers: { 'X-API-Key': apiKey },
   })
   if (!res.ok) throw new Error(`Utilities API ${res.status} — ${path}`)