diff --git a/CHANGELOG.md b/CHANGELOG.md
index 933b832..e2cf476 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- Unit tests for mail account endpoints (`test_mail_accounts.py`): 30 tests covering CRUD, toggle, pull-now, test connection, auto-detect, processing runs, and processing logs
 - Unit tests for authentication endpoints (`test_auth.py`): 22 tests covering register, login, Google OAuth, authorize-url, and helper functions
 
 ## v0.6.0 (2026-03-29)
diff --git a/backend/tests/unit/test_mail_accounts.py b/backend/tests/unit/test_mail_accounts.py
new file mode 100644
index 0000000..d3e5ef5
--- /dev/null
+++ b/backend/tests/unit/test_mail_accounts.py
@@ -0,0 +1,774 @@
+"""
+Unit tests for mail account endpoints (backend/app/api/v1/endpoints/mail_accounts.py).
+
+All tests mock the database session and auth dependencies so no real
+PostgreSQL instance is required.
+"""
+
+import pytest
+from datetime import datetime, timezone
+from unittest.mock import AsyncMock, MagicMock, patch
+
+from httpx import AsyncClient, ASGITransport
+
+from app.main import create_application
+from app.core.database import get_db
+from app.core.deps import get_current_active_user
+from app.models.database_models import (
+    User,
+    MailAccount,
+    ProcessingRun,
+    ProcessingLog,
+    SubscriptionPlan,
+    SubscriptionTier,
+    AccountStatus,
+)
+
+BASE = "/api/v1/mail-accounts"
+
+# ── helpers ──────────────────────────────────────────────────────────────
+
+
+def _make_user(**overrides) -> MagicMock:
+    """Return a MagicMock that behaves like a User ORM instance."""
+    defaults = dict(
+        id=1,
+        email="user@example.com",
+        hashed_password="hashed",
+        full_name="Test User",
+        is_active=True,
+        is_superuser=False,
+        subscription_tier=SubscriptionTier.FREE,
+        subscription_status="active",
+        google_id=None,
+        oauth_provider=None,
+        last_login_at=None,
+        created_at=datetime.now(timezone.utc),
+        updated_at=datetime.now(timezone.utc),
+        stripe_customer_id=None,
+        stripe_subscription_id=None,
+        subscription_expires_at=None,
+    )
+    defaults.update(overrides)
+    user = MagicMock(spec=User)
+    for k, v in defaults.items():
+        setattr(user, k, v)
+    return user
+
+
+def _make_superuser(**overrides) -> MagicMock:
+    return _make_user(is_superuser=True, **overrides)
+
+
+def _make_account(**overrides) -> MagicMock:
+    """Return a MagicMock that behaves like a MailAccount ORM instance."""
+    defaults = dict(
+        id=10,
+        user_id=1,
+        name="Test Account",
+        email_address="test@example.com",
+        protocol="pop3_ssl",
+        host="pop.example.com",
+        port=995,
+        use_ssl=True,
+        use_tls=False,
+        username="test@example.com",
+        encrypted_password="encrypted_pass",
+        forward_to="me@gmail.com",
+        delivery_method="gmail_api",
+        status="active",
+        is_enabled=True,
+        check_interval_minutes=5,
+        max_emails_per_check=50,
+        delete_after_forward=True,
+        provider_name="Gmail",
+        auto_detected=False,
+        total_emails_processed=100,
+        total_emails_failed=2,
+        last_check_at=datetime.now(timezone.utc),
+        last_successful_check_at=datetime.now(timezone.utc),
+        last_error_at=None,
+        last_error_message=None,
+        created_at=datetime.now(timezone.utc),
+        updated_at=datetime.now(timezone.utc),
+    )
+    defaults.update(overrides)
+    account = MagicMock(spec=MailAccount)
+    for k, v in defaults.items():
+        setattr(account, k, v)
+    return account
+
+
+def _make_run(**overrides) -> MagicMock:
+    """Return a MagicMock that behaves like a ProcessingRun ORM instance."""
+    defaults = dict(
+        id=100,
+        mail_account_id=10,
+        started_at=datetime.now(timezone.utc),
+        completed_at=datetime.now(timezone.utc),
+        duration_seconds=1.5,
+        emails_fetched=5,
+        emails_forwarded=4,
+        emails_failed=1,
+        status="completed",
+        error_message=None,
+    )
+    defaults.update(overrides)
+    run = MagicMock(spec=ProcessingRun)
+    for k, v in defaults.items():
+        setattr(run, k, v)
+    return run
+
+
+def _make_log(**overrides) -> MagicMock:
+    """Return a MagicMock that behaves like a ProcessingLog ORM instance."""
+    defaults = dict(
+        id=200,
+        user_id=1,
+        mail_account_id=10,
+        processing_run_id=100,
+        timestamp=datetime.now(timezone.utc),
+        level="INFO",
+        message="Processed email",
+        email_subject="Hello",
+        email_from="sender@example.com",
+        email_size_bytes=1024,
+        success=True,
+        error_details=None,
+    )
+    defaults.update(overrides)
+    log = MagicMock(spec=ProcessingLog)
+    for k, v in defaults.items():
+        setattr(log, k, v)
+    return log
+
+
+def _scalar_one_or_none(value):
+    """Create a mock result whose .scalar_one_or_none() returns *value*."""
+    result = MagicMock()
+    result.scalar_one_or_none.return_value = value
+    return result
+
+
+def _scalar_one(value):
+    result = MagicMock()
+    result.scalar_one.return_value = value
+    return result
+
+
+def _scalars_all(values):
+    result = MagicMock()
+    scalars = MagicMock()
+    scalars.all.return_value = values
+    result.scalars.return_value = scalars
+    return result
+
+
+# ── fixtures ─────────────────────────────────────────────────────────────
+
+
+@pytest.fixture
+def app():
+    return create_application()
+
+
+@pytest.fixture
+def regular_user():
+    return _make_user()
+
+
+@pytest.fixture
+def superuser():
+    return _make_superuser()
+
+
+@pytest.fixture
+def mock_db():
+    db = AsyncMock()
+    db.commit = AsyncMock()
+    db.refresh = AsyncMock()
+    db.delete = AsyncMock()
+    db.add = MagicMock()
+    return db
+
+
+@pytest.fixture
+async def client(app, regular_user, mock_db):
+    """AsyncClient where the caller is a regular user and db is mocked."""
+
+    async def _override_user():
+        return regular_user
+
+    async def _override_db():
+        yield mock_db
+
+    app.dependency_overrides[get_current_active_user] = _override_user
+    app.dependency_overrides[get_db] = _override_db
+
+    transport = ASGITransport(app=app)
+    async with AsyncClient(transport=transport, base_url="http://test") as c:
+        yield c
+
+    app.dependency_overrides.clear()
+
+
+@pytest.fixture
+async def superuser_client(app, superuser, mock_db):
+    """AsyncClient where the caller is a superuser and db is mocked."""
+
+    async def _override_user():
+        return superuser
+
+    async def _override_db():
+        yield mock_db
+
+    app.dependency_overrides[get_current_active_user] = _override_user
+    app.dependency_overrides[get_db] = _override_db
+
+    transport = ASGITransport(app=app)
+    async with AsyncClient(transport=transport, base_url="http://test") as c:
+        yield c
+
+    app.dependency_overrides.clear()
+
+
+# ── account payload helper ───────────────────────────────────────────────
+
+VALID_ACCOUNT_PAYLOAD = dict(
+    name="My Account",
+    email_address="inbox@example.com",
+    protocol="pop3_ssl",
+    host="pop.example.com",
+    port=995,
+    use_ssl=True,
+    use_tls=False,
+    username="inbox@example.com",
+    password="secret",
+    forward_to="me@gmail.com",
+    delivery_method="gmail_api",
+    is_enabled=True,
+    check_interval_minutes=5,
+    max_emails_per_check=50,
+    delete_after_forward=True,
+    provider_name="Gmail",
+)
+
+
+# ── tests: create mail account ──────────────────────────────────────────
+
+
+class TestCreateMailAccount:
+    """POST /api/v1/mail-accounts"""
+
+    @patch("app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="enc")
+    async def test_create_superuser_bypasses_limit(
+        self, mock_encrypt, superuser_client, mock_db
+    ):
+        """Superusers skip the subscription-limit check entirely."""
+        mock_db.refresh = AsyncMock(side_effect=lambda obj: None)
+        created = {}
+
+        def capture_add(obj):
+            created["obj"] = obj
+            # Give the added object all the response fields
+            for k, v in {
+                "id": 10,
+                "user_id": 1,
+                "status": "active",
+                "auto_detected": False,
+                "total_emails_processed": 0,
+                "total_emails_failed": 0,
+                "last_check_at": None,
+                "last_successful_check_at": None,
+                "last_error_at": None,
+                "last_error_message": None,
+                "created_at": datetime.now(timezone.utc),
+                "updated_at": datetime.now(timezone.utc),
+            }.items():
+                setattr(obj, k, v)
+
+        mock_db.add = MagicMock(side_effect=capture_add)
+
+        resp = await superuser_client.post(BASE, json=VALID_ACCOUNT_PAYLOAD)
+        assert resp.status_code == 201
+        data = resp.json()
+        assert data["name"] == "My Account"
+        assert data["email_address"] == "inbox@example.com"
+        mock_encrypt.assert_called_once_with("secret")
+        mock_db.commit.assert_called_once()
+
+    @patch("app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="enc")
+    async def test_create_regular_user_within_limit(
+        self, mock_encrypt, client, mock_db
+    ):
+        """Regular user under their plan limit can create an account."""
+        # 1st execute: count existing accounts (returns 0 accounts)
+        # 2nd execute: fetch subscription plan
+        plan = MagicMock(spec=SubscriptionPlan)
+        plan.max_mail_accounts = 5
+
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalars_all([]),  # existing accounts
+                _scalar_one_or_none(plan),  # subscription plan
+            ]
+        )
+
+        def capture_add(obj):
+            for k, v in {
+                "id": 10,
+                "user_id": 1,
+                "status": "active",
+                "auto_detected": False,
+                "total_emails_processed": 0,
+                "total_emails_failed": 0,
+                "last_check_at": None,
+                "last_successful_check_at": None,
+                "last_error_at": None,
+                "last_error_message": None,
+                "created_at": datetime.now(timezone.utc),
+                "updated_at": datetime.now(timezone.utc),
+            }.items():
+                setattr(obj, k, v)
+
+        mock_db.add = MagicMock(side_effect=capture_add)
+
+        resp = await client.post(BASE, json=VALID_ACCOUNT_PAYLOAD)
+        assert resp.status_code == 201
+        mock_encrypt.assert_called_once_with("secret")
+
+    @patch("app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="enc")
+    async def test_create_subscription_limit_reached(
+        self, mock_encrypt, client, mock_db
+    ):
+        """402 when account limit is reached."""
+        existing = [_make_account(id=i) for i in range(1)]
+        plan = MagicMock(spec=SubscriptionPlan)
+        plan.max_mail_accounts = 1
+
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalars_all(existing),  # existing accounts (1 already)
+                _scalar_one_or_none(plan),  # plan says max=1
+            ]
+        )
+
+        resp = await client.post(BASE, json=VALID_ACCOUNT_PAYLOAD)
+        assert resp.status_code == 402
+        assert "limit" in resp.json()["detail"].lower()
+
+    @patch("app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="enc")
+    async def test_create_uses_db_plan_limit(self, mock_encrypt, client, mock_db):
+        """When a SubscriptionPlan exists in the DB, use its max_mail_accounts."""
+        plan = MagicMock(spec=SubscriptionPlan)
+        plan.max_mail_accounts = 3
+
+        existing = [_make_account(id=i) for i in range(3)]
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalars_all(existing),  # 3 existing
+                _scalar_one_or_none(plan),  # plan limit = 3
+            ]
+        )
+
+        resp = await client.post(BASE, json=VALID_ACCOUNT_PAYLOAD)
+        assert resp.status_code == 402
+
+    @patch("app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="enc")
+    async def test_create_fallback_tier_limit_when_no_plan(
+        self, mock_encrypt, client, mock_db
+    ):
+        """When no SubscriptionPlan row exists, falls back to settings tier limits."""
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalars_all([]),  # 0 existing accounts
+                _scalar_one_or_none(None),  # no plan in DB → fallback
+            ]
+        )
+
+        def capture_add(obj):
+            for k, v in {
+                "id": 10,
+                "user_id": 1,
+                "status": "active",
+                "auto_detected": False,
+                "total_emails_processed": 0,
+                "total_emails_failed": 0,
+                "last_check_at": None,
+                "last_successful_check_at": None,
+                "last_error_at": None,
+                "last_error_message": None,
+                "created_at": datetime.now(timezone.utc),
+                "updated_at": datetime.now(timezone.utc),
+            }.items():
+                setattr(obj, k, v)
+
+        mock_db.add = MagicMock(side_effect=capture_add)
+
+        resp = await client.post(BASE, json=VALID_ACCOUNT_PAYLOAD)
+        # free tier default is 1, and 0 existing → should succeed
+        assert resp.status_code == 201
+
+
+# ── tests: list mail accounts ───────────────────────────────────────────
+
+
+class TestListMailAccounts:
+    """GET /api/v1/mail-accounts"""
+
+    async def test_list_accounts(self, client, mock_db):
+        accounts = [_make_account(id=1), _make_account(id=2)]
+        mock_db.execute = AsyncMock(return_value=_scalars_all(accounts))
+
+        resp = await client.get(BASE)
+        assert resp.status_code == 200
+        data = resp.json()
+        assert len(data) == 2
+
+
+# ── tests: get mail account ─────────────────────────────────────────────
+
+
+class TestGetMailAccount:
+    """GET /api/v1/mail-accounts/{account_id}"""
+
+    async def test_get_account_success(self, client, mock_db):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.get(f"{BASE}/10")
+        assert resp.status_code == 200
+        assert resp.json()["id"] == 10
+
+    async def test_get_account_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.get(f"{BASE}/999")
+        assert resp.status_code == 404
+
+
+# ── tests: update mail account ──────────────────────────────────────────
+
+
+class TestUpdateMailAccount:
+    """PUT /api/v1/mail-accounts/{account_id}"""
+
+    async def test_update_account_success(self, client, mock_db):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.put(f"{BASE}/10", json={"name": "Updated Name"})
+        assert resp.status_code == 200
+        mock_db.commit.assert_called()
+
+    @patch(
+        "app.api.v1.endpoints.mail_accounts.encrypt_credential", return_value="new_enc"
+    )
+    async def test_update_account_with_password(self, mock_encrypt, client, mock_db):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.put(f"{BASE}/10", json={"password": "newpass"})
+        assert resp.status_code == 200
+        mock_encrypt.assert_called_once_with("newpass")
+        # Verify encrypted_password was set on the account
+        assert account.encrypted_password == "new_enc"
+
+    async def test_update_account_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.put(f"{BASE}/999", json={"name": "X"})
+        assert resp.status_code == 404
+
+
+# ── tests: delete mail account ──────────────────────────────────────────
+
+
+class TestDeleteMailAccount:
+    """DELETE /api/v1/mail-accounts/{account_id}"""
+
+    async def test_delete_account_success(self, client, mock_db):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.delete(f"{BASE}/10")
+        assert resp.status_code == 204
+        mock_db.delete.assert_called_once_with(account)
+        mock_db.commit.assert_called()
+
+    async def test_delete_account_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.delete(f"{BASE}/999")
+        assert resp.status_code == 404
+
+
+# ── tests: toggle mail account ──────────────────────────────────────────
+
+
+class TestToggleMailAccount:
+    """PATCH /api/v1/mail-accounts/{account_id}/toggle"""
+
+    async def test_toggle_enable_resets_error(self, client, mock_db):
+        """Toggling an ERROR account to enabled resets status to ACTIVE."""
+        account = _make_account(is_enabled=False, status=AccountStatus.ERROR)
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.patch(f"{BASE}/10/toggle")
+        assert resp.status_code == 200
+        # After toggle: is_enabled=True and status reset from ERROR → ACTIVE
+        assert account.is_enabled is True
+        assert account.status == AccountStatus.ACTIVE
+        mock_db.commit.assert_called()
+
+    async def test_toggle_disable(self, client, mock_db):
+        """Toggling an enabled account disables it."""
+        account = _make_account(is_enabled=True, status=AccountStatus.ACTIVE)
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.patch(f"{BASE}/10/toggle")
+        assert resp.status_code == 200
+        assert account.is_enabled is False
+
+    async def test_toggle_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.patch(f"{BASE}/999/toggle")
+        assert resp.status_code == 404
+
+
+# ── tests: pull now ─────────────────────────────────────────────────────
+
+
+class TestPullNow:
+    """POST /api/v1/mail-accounts/{account_id}/pull-now"""
+
+    @patch("app.api.v1.endpoints.mail_accounts.process_mail_account_task")
+    async def test_pull_now_success(self, mock_task, client, mock_db):
+        account = _make_account(is_enabled=True)
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.post(f"{BASE}/10/pull-now")
+        assert resp.status_code == 202
+        assert "queued" in resp.json()["message"].lower()
+        mock_task.delay.assert_called_once_with(10)
+
+    @patch("app.api.v1.endpoints.mail_accounts.process_mail_account_task")
+    async def test_pull_now_disabled_account(self, mock_task, client, mock_db):
+        account = _make_account(is_enabled=False)
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.post(f"{BASE}/10/pull-now")
+        assert resp.status_code == 409
+        assert "disabled" in resp.json()["detail"].lower()
+        mock_task.delay.assert_not_called()
+
+    @patch("app.api.v1.endpoints.mail_accounts.process_mail_account_task")
+    async def test_pull_now_not_found(self, mock_task, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.post(f"{BASE}/999/pull-now")
+        assert resp.status_code == 404
+
+
+# ── tests: test connection (new) ────────────────────────────────────────
+
+
+class TestTestConnection:
+    """POST /api/v1/mail-accounts/test"""
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailProcessor")
+    async def test_connection_success(self, mock_processor_cls, client):
+        instance = mock_processor_cls.return_value
+        instance.test_connection = AsyncMock(
+            return_value=(True, "Connection successful")
+        )
+
+        payload = dict(
+            host="pop.example.com",
+            port=995,
+            protocol="pop3_ssl",
+            username="user@example.com",
+            password="pass",
+            use_ssl=True,
+            use_tls=False,
+        )
+        resp = await client.post(f"{BASE}/test", json=payload)
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["success"] is True
+        assert data["message"] == "Connection successful"
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailProcessor")
+    async def test_connection_failure(self, mock_processor_cls, client):
+        instance = mock_processor_cls.return_value
+        instance.test_connection = AsyncMock(return_value=(False, "Connection refused"))
+
+        payload = dict(
+            host="pop.example.com",
+            port=995,
+            protocol="pop3_ssl",
+            username="user@example.com",
+            password="pass",
+            use_ssl=True,
+            use_tls=False,
+        )
+        resp = await client.post(f"{BASE}/test", json=payload)
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["success"] is False
+        assert data["message"] == "Connection refused"
+
+
+# ── tests: test existing connection ─────────────────────────────────────
+
+
+class TestTestExistingConnection:
+    """POST /api/v1/mail-accounts/{account_id}/test"""
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailProcessor")
+    @patch(
+        "app.api.v1.endpoints.mail_accounts.decrypt_credential",
+        return_value="decrypted_pass",
+    )
+    async def test_existing_connection_success(
+        self, mock_decrypt, mock_processor_cls, client, mock_db
+    ):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        instance = mock_processor_cls.return_value
+        instance.test_connection = AsyncMock(return_value=(True, "Connected"))
+
+        resp = await client.post(f"{BASE}/10/test")
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["success"] is True
+        mock_decrypt.assert_called_once_with("encrypted_pass")
+        mock_processor_cls.assert_called_once_with(account, "decrypted_pass")
+
+    async def test_existing_connection_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.post(f"{BASE}/999/test")
+        assert resp.status_code == 404
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailProcessor")
+    @patch(
+        "app.api.v1.endpoints.mail_accounts.decrypt_credential",
+        side_effect=Exception("Decryption failed"),
+    )
+    async def test_existing_connection_decrypt_failure(
+        self, mock_decrypt, mock_processor_cls, client, mock_db
+    ):
+        account = _make_account()
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(account))
+
+        resp = await client.post(f"{BASE}/10/test")
+        assert resp.status_code == 500
+        assert "decrypt" in resp.json()["detail"].lower()
+
+
+# ── tests: auto-detect ──────────────────────────────────────────────────
+
+
+class TestAutoDetect:
+    """POST /api/v1/mail-accounts/auto-detect"""
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailServerAutoDetect")
+    async def test_auto_detect_success(self, mock_auto_cls, client):
+        mock_auto_cls.detect.return_value = [
+            {"host": "pop.gmail.com", "port": 995, "protocol": "pop3_ssl"}
+        ]
+
+        resp = await client.post(
+            f"{BASE}/auto-detect",
+            json={"email_address": "user@gmail.com"},
+        )
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["success"] is True
+        assert len(data["suggestions"]) == 1
+        mock_auto_cls.detect.assert_called_once_with("user@gmail.com")
+
+    @patch("app.api.v1.endpoints.mail_accounts.MailServerAutoDetect")
+    async def test_auto_detect_no_suggestions(self, mock_auto_cls, client):
+        mock_auto_cls.detect.return_value = []
+
+        resp = await client.post(
+            f"{BASE}/auto-detect",
+            json={"email_address": "user@unknown-domain.xyz"},
+        )
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["success"] is False
+        assert data["suggestions"] == []
+
+
+# ── tests: processing runs ──────────────────────────────────────────────
+
+
+class TestListProcessingRuns:
+    """GET /api/v1/mail-accounts/{account_id}/processing-runs"""
+
+    async def test_list_runs_success(self, client, mock_db):
+        account = _make_account()
+        run = _make_run()
+
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalar_one_or_none(account),  # ownership check
+                _scalar_one(1),  # count
+                _scalars_all([run]),  # run data
+            ]
+        )
+
+        resp = await client.get(f"{BASE}/10/processing-runs")
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["total"] == 1
+        assert data["page"] == 1
+        assert len(data["items"]) == 1
+        assert data["items"][0]["id"] == 100
+        assert data["items"][0]["account_name"] == "Test Account"
+        assert data["items"][0]["account_email"] == "test@example.com"
+
+    async def test_list_runs_account_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.get(f"{BASE}/999/processing-runs")
+        assert resp.status_code == 404
+
+
+# ── tests: processing logs ──────────────────────────────────────────────
+
+
+class TestListProcessingLogs:
+    """GET /api/v1/mail-accounts/{account_id}/logs"""
+
+    async def test_list_logs_success(self, client, mock_db):
+        account = _make_account()
+        log = _make_log()
+
+        mock_db.execute = AsyncMock(
+            side_effect=[
+                _scalar_one_or_none(account),  # ownership check
+                _scalar_one(1),  # count
+                _scalars_all([log]),  # log data
+            ]
+        )
+
+        resp = await client.get(f"{BASE}/10/logs")
+        assert resp.status_code == 200
+        data = resp.json()
+        assert data["total"] == 1
+        assert len(data["items"]) == 1
+        assert data["items"][0]["id"] == 200
+        assert data["items"][0]["level"] == "INFO"
+        assert data["items"][0]["message"] == "Processed email"
+
+    async def test_list_logs_account_not_found(self, client, mock_db):
+        mock_db.execute = AsyncMock(return_value=_scalar_one_or_none(None))
+
+        resp = await client.get(f"{BASE}/999/logs")
+        assert resp.status_code == 404
diff --git a/docs/TODO.md b/docs/TODO.md
index eb70ab5..5ecdcce 100644
--- a/docs/TODO.md
+++ b/docs/TODO.md
@@ -123,6 +123,7 @@ Comprehensive task breakdown for repository improvements and production readines
 
 ### In Progress 🔨
 - [x] Write unit tests for authentication (22 tests covering register, login, Google OAuth, authorize-url, and helper functions)
+- [x] Write unit tests for mail account endpoints (30 tests covering CRUD, toggle, pull-now, test connection, auto-detect, processing runs/logs)
 - [ ] Write unit tests for mail processing
 - [ ] Write integration tests for API endpoints