diff --git a/fusion_accounting_followup/tests/__init__.py b/fusion_accounting_followup/tests/__init__.py
index 583b044b..308d8a54 100644
--- a/fusion_accounting_followup/tests/__init__.py
+++ b/fusion_accounting_followup/tests/__init__.py
@@ -15,3 +15,4 @@ from . import test_followup_adapter
 from . import test_followup_tools
 from . import test_followup_cron
 from . import test_engine_property
+from . import test_followup_full_flow
diff --git a/fusion_accounting_followup/tests/test_followup_full_flow.py b/fusion_accounting_followup/tests/test_followup_full_flow.py
new file mode 100644
index 00000000..8a65e12f
--- /dev/null
+++ b/fusion_accounting_followup/tests/test_followup_full_flow.py
@@ -0,0 +1,84 @@
+"""End-to-end integration: scan -> escalate -> send -> reset."""
+
+from datetime import date, timedelta
+from odoo.tests.common import TransactionCase
+from odoo.tests import tagged
+
+
+@tagged('post_install', '-at_install', 'integration')
+class TestFollowupFullFlow(TransactionCase):
+
+    def setUp(self):
+        super().setUp()
+        self.engine = self.env['fusion.followup.engine']
+        self.partner = self.env['res.partner'].create({
+            'name': 'Full Flow Partner', 'email': 'flow@test.local',
+        })
+        for seq, name, days, tone in [(701, 'FlowReminder', 7, 'gentle'),
+                                      (702, 'FlowWarning', 30, 'firm'),
+                                      (703, 'FlowLegal', 60, 'legal')]:
+            self.env['fusion.followup.level'].create({
+                'name': name, 'sequence': seq,
+                'delay_days': days, 'tone': tone,
+            })
+
+        line = self.env['account.move.line'].search([
+            ('parent_state', '=', 'posted'),
+            ('account_id.account_type', '=', 'asset_receivable'),
+            ('reconciled', '=', False),
+            ('amount_residual', '>', 0),
+        ], limit=1)
+        if not line:
+            self.skipTest("No posted unreconciled receivable lines in test DB")
+        line.write({
+            'partner_id': self.partner.id,
+            'date_maturity': date.today() - timedelta(days=20),
+        })
+
+    def test_full_flow_scan_send_reset(self):
+        level = self.engine.compute_followup_level(self.partner)
+        self.assertTrue(level)
+        self.assertGreater(level.delay_days, 0)
+
+        Run = self.env['fusion.followup.run']
+        before = Run.search_count([('partner_id', '=', self.partner.id)])
+        result = self.engine.send_followup_email(self.partner, force=True)
+        after = Run.search_count([('partner_id', '=', self.partner.id)])
+        self.assertGreater(after, before)
+        self.assertIn(result['status'], ('sent', 'manual_review'))
+
+        self.engine.pause_followup(self.partner,
+                                   until_date=date.today() + timedelta(days=14))
+        result_paused = self.engine.send_followup_email(self.partner)
+        self.assertTrue(result_paused['status'].startswith('paused'))
+
+        self.engine.reset_followup(self.partner)
+        self.partner.invalidate_recordset(['fusion_followup_status'])
+        self.assertEqual(self.partner.fusion_followup_status, 'no_action')
+
+    def test_escalate_advances_to_next_level(self):
+        Level = self.env['fusion.followup.level']
+        level1 = Level.search([('sequence', '=', 701)], limit=1)
+        self.engine.send_followup_email(self.partner, level=level1, force=True)
+        self.partner.invalidate_recordset(['fusion_followup_last_level_id'])
+        result = self.engine.escalate_to_next_level(self.partner)
+        self.assertIn('partner_id', result)
+        self.partner.invalidate_recordset(['fusion_followup_last_level_id'])
+        if self.partner.fusion_followup_last_level_id:
+            self.assertGreaterEqual(self.partner.fusion_followup_last_level_id.sequence, 702)
+
+    def test_text_cache_reused_on_repeat(self):
+        Cache = self.env['fusion.followup.text.cache']
+        self.engine.send_followup_email(self.partner, force=True)
+        after_first = Cache.search_count([('partner_id', '=', self.partner.id)])
+        self.engine.send_followup_email(self.partner, force=True)
+        after_second = Cache.search_count([('partner_id', '=', self.partner.id)])
+        self.assertEqual(after_first, after_second)
+
+    def test_history_records_each_send(self):
+        Run = self.env['fusion.followup.run']
+        before = Run.search_count([('partner_id', '=', self.partner.id)])
+        self.engine.send_followup_email(self.partner, force=True)
+        self.engine.send_followup_email(self.partner, force=True)
+        after = Run.search_count([('partner_id', '=', self.partner.id)])
+        self.assertEqual(after - before, 2)