diff --git a/routes/analytics.cts b/routes/analytics.cts
index 695b4ed..075eb9d 100644
--- a/routes/analytics.cts
+++ b/routes/analytics.cts
@@ -2,13 +2,12 @@
 import type { Req, Res, Next } from '../types/http';
 const express = require('express');
 const router = express.Router();
-const { standardizeError } = require('../middleware/errorFormatter.cts');
+const { ValidationError } = require('../utils/apiError.cts');
 const { getAnalyticsSummary } = require('../services/analyticsService.cts');
 
 router.get('/summary', (req: Req, res: Res) => {
   const result = getAnalyticsSummary(req.user.id, req.query);
-  if (result.error)
-    return res.status(400).json(standardizeError(result.error, 'VALIDATION_ERROR', 'month'));
+  if (result.error) throw ValidationError(result.error, 'month');
   res.json(result);
 });
 
diff --git a/routes/tracker.cts b/routes/tracker.cts
index 2513d60..2f6a8d6 100644
--- a/routes/tracker.cts
+++ b/routes/tracker.cts
@@ -3,42 +3,23 @@ import type { Req, Res, Next } from '../types/http';
 const express = require('express');
 const router = express.Router();
 const { getTracker, getUpcomingBills, getOverdueCount } = require('../services/trackerService.cts');
-const { standardizeError } = require('../middleware/errorFormatter.cts');
+const { ApiError, ValidationError } = require('../utils/apiError.cts');
 
 // GET /api/tracker/overdue-count — lightweight count for sidebar badge
 router.get('/overdue-count', (req: Req, res: Res) => {
-  try {
-    res.json(getOverdueCount(req.user.id));
-  } catch (err) {
-    console.error('[tracker/overdue-count]', err.message);
-    res.status(500).json(standardizeError('Failed to load overdue count', 'INTERNAL_ERROR'));
-  }
+  res.json(getOverdueCount(req.user.id));
 });
 
 // GET /api/tracker?year=2026&month=5
 router.get('/', (req: Req, res: Res) => {
-  try {
-    const result = getTracker(req.user.id, req.query);
-    if (result.error) {
-      return res
-        .status(result.status || 400)
-        .json(standardizeError(result.error, 'VALIDATION_ERROR'));
-    }
-    res.json(result);
-  } catch (err) {
-    console.error('[tracker]', err.message);
-    res.status(500).json(standardizeError('Failed to load tracker data', 'INTERNAL_ERROR'));
-  }
+  const result = getTracker(req.user.id, req.query);
+  if (result.error) throw new ApiError('VALIDATION_ERROR', result.error, result.status || 400);
+  res.json(result);
 });
 
 // GET /api/tracker/upcoming?days=30
 router.get('/upcoming', (req: Req, res: Res) => {
-  try {
-    res.json(getUpcomingBills(req.user.id, req.query));
-  } catch (err) {
-    console.error('[tracker/upcoming]', err.message);
-    res.status(500).json(standardizeError('Failed to load upcoming bills', 'INTERNAL_ERROR'));
-  }
+  res.json(getUpcomingBills(req.user.id, req.query));
 });
 
 module.exports = router;
diff --git a/tests/trackerService.test.js b/tests/trackerService.test.js
index b8cb16a..b964eeb 100644
--- a/tests/trackerService.test.js
+++ b/tests/trackerService.test.js
@@ -164,7 +164,15 @@ test('GET /tracker returns a standardized error for an invalid month', async ()
         resolve({ status: this.statusCode, data: d });
       },
     };
-    handler(req, res);
+    // Handlers now throw ApiError; simulate the terminal error handler.
+    try {
+      handler(req, res);
+    } catch (err) {
+      resolve({
+        status: err.status || 500,
+        data: { error: err.code, message: err.message, code: err.code, field: err.field ?? null },
+      });
+    }
   });
   assert.equal(result.status, 400);
   assert.equal(result.data.code, 'VALIDATION_ERROR', 'standardized shape, not a plain {error}');