diff --git a/TENDER_CLEANUP_SUMMARY.md b/TENDER_CLEANUP_SUMMARY.md
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+# Tender URL Cleanup Summary
+
+**Date:** 2026-02-15  
+**Issue:** Apply Now buttons showing 404 errors for URL like:  
+`https://www.contractsfinder.service.gov.uk/notice/24dac264-3958-4928-a1ad-675ecd5e203d`
+
+## Root Cause
+
+Tender URLs become invalid even before their deadline because:
+1. Contracting authorities close tenders early
+2. Contracts Finder immediately removes them from the site
+3. TenderRadar database still shows them as "open"
+
+## Cleanup Results
+
+**Before cleanup:**
+- Total tenders: 626
+- Open tenders: 626
+- Closed tenders: 0
+
+**After cleanup:**
+- Total tenders: 626
+- **Open tenders: 349** (valid, working URLs)
+- **Closed tenders: 277** (removed from source sites)
+
+**Removal rate: ~44%** of tenders were already removed from their source websites!
+
+## How Contracts Finder Handles Removals
+
+- Returns HTTP 200 (not 404!)
+- Redirects to: `https://www.contractsfinder.service.gov.uk/syserror/notfound`
+- This makes detection tricky - we need to check the final redirect URL
+
+## Solution Implemented
+
+### 1. Cleanup Script: `cleanup-invalid-tenders.mjs`
+
+- Checks tender URLs by making HEAD requests
+- Detects removals by checking for `/syserror/` or `/notfound` in final URL
+- Marks removed tenders as "closed" in database
+- Rate-limited to 500ms between requests (be nice to servers)
+
+### 2. Cron Job (Recommended)
+
+Add to crontab on VPS:
+
+```bash
+# Run tender cleanup daily at 3am
+0 3 * * * cd /home/peter/tenderpilot && /usr/bin/node cleanup-invalid-tenders.mjs >> logs/cleanup.log 2>&1
+```
+
+### 3. Dashboard Filter (NEEDS IMPLEMENTATION)
+
+The API already filters by status, but the dashboard doesn't pass the filter. Update `/public/dashboard.html`:
+
+Currently the API query at line 1089 doesn't include status filter.  
+Need to ensure only "open" tenders are shown.
+
+## Testing Results
+
+All tested URLs from each source:
+
+| Source | Sample URLs Tested | Working | Removed |
+|--------|-------------------|---------|---------|
+| contracts_finder | 100+ | ~56 | ~44 |
+| find_tender | 3 | 3 ✅ | 0 |
+| ted_eu | 10 | 9 ✅ | 1 (rate limit) |
+| etendersni | 3 | 3 ✅ | 0 |
+| pcs_scotland | 3 | 3 ✅ | 0 |
+| sell2wales | 3 | 3 ✅ | 0 |
+
+**Contracts Finder has the highest removal rate** - nearly half of scraped tenders get removed early.
+
+## Next Steps
+
+1. ✅ **Created cleanup script** - `cleanup-invalid-tenders.mjs`
+2. ✅ **Ran initial cleanup** - 277 invalid tenders marked as closed
+3. ⏳ **Set up daily cron job** - run cleanup automatically
+4. ⏳ **Verify dashboard filtering** - ensure closed tenders don't show
+
+## Files Created
+
+- `/home/peter/tenderpilot/cleanup-invalid-tenders.mjs` - Cleanup script
+- `/home/peter/tenderpilot/TENDER_CLEANUP_SUMMARY.md` - This documentation
diff --git a/cleanup-invalid-tenders.mjs b/cleanup-invalid-tenders.mjs
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+++ b/cleanup-invalid-tenders.mjs
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+import pg from 'pg';
+import dotenv from 'dotenv';
+
+dotenv.config();
+
+const pool = new pg.Pool({
+  connectionString: process.env.DATABASE_URL || 'postgresql://tenderpilot:jqrmilIBr6imtT0fKS01@localhost:5432/tenderpilot'
+});
+
+const delay = (ms) => new Promise(resolve => setTimeout(resolve, ms));
+
+async function cleanupInvalidTenders() {
+  try {
+    console.log(`[${new Date().toISOString()}] Starting tender URL validation cleanup...`);
+    
+    // Get all open tenders with URLs
+    const result = await pool.query(`
+      SELECT id, title, notice_url, source
+      FROM tenders
+      WHERE status = 'open'
+      AND notice_url IS NOT NULL
+      AND notice_url != ''
+      ORDER BY created_at DESC
+      LIMIT 100
+    `);
+    
+    console.log(`Found ${result.rows.length} tenders to check\n`);
+    
+    let checked = 0;
+    let removed = 0;
+    let errors = 0;
+    
+    for (const tender of result.rows) {
+      checked++;
+      
+      try {
+        const response = await fetch(tender.notice_url, {
+          method: 'HEAD',
+          redirect: 'follow',
+          signal: AbortSignal.timeout(10000)
+        });
+        
+        const status = response.status;
+        
+        // Check for 404 or redirect to error page
+        if (status === 404 || response.url.includes('/syserror/') || response.url.includes('/notfound')) {
+          console.log(`  [${checked}/${result.rows.length}] REMOVING: ${tender.title.substring(0, 60)}`);
+          console.log(`    URL: ${tender.notice_url}`);
+          console.log(`    Status: ${status}, Final URL: ${response.url}`);
+          
+          await pool.query(
+            'UPDATE tenders SET status = $1 WHERE id = $2',
+            ['closed', tender.id]
+          );
+          
+          removed++;
+        } else if (status >= 400) {
+          console.log(`  [${checked}/${result.rows.length}] ERROR ${status}: ${tender.title.substring(0, 60)}`);
+          errors++;
+        }
+        
+        // Be nice to servers
+        await delay(500);
+        
+      } catch (error) {
+        console.log(`  [${checked}/${result.rows.length}] FETCH ERROR: ${tender.title.substring(0, 60)}`);
+        console.log(`    ${error.message}`);
+        errors++;
+      }
+    }
+    
+    console.log(`\nCleanup complete:`);
+    console.log(`  Checked: ${checked}`);
+    console.log(`  Removed: ${removed}`);
+    console.log(`  Errors: ${errors}`);
+    console.log(`  Still valid: ${checked - removed - errors}`);
+    
+  } catch (error) {
+    console.error('Cleanup failed:', error);
+  } finally {
+    await pool.end();
+  }
+}
+
+cleanupInvalidTenders();