diff --git a/intrastat_base/tests/common.py b/intrastat_base/tests/common.py
index 640c62a..58a2491 100644
--- a/intrastat_base/tests/common.py
+++ b/intrastat_base/tests/common.py
@@ -52,11 +52,6 @@ class IntrastatCommon(object):
 
         cls.shipping_cost = cls.env.ref("intrastat_base.shipping_costs_exclude")
         cls._load_test_declaration()
-        cls.declaration_test_obj = cls.env["intrastat.declaration.test"]
-        cls._load_xml("intrastat_base", "tests/data/mail_template.xml")
-        cls.mail_template_id = (
-            "intrastat_base.base_intrastat_product_reminder_email_template"
-        )
 
     @classmethod
     def tearDownClass(cls):
diff --git a/intrastat_base/tests/test_all.py b/intrastat_base/tests/test_all.py
index f25e1dc..cc7b203 100644
--- a/intrastat_base/tests/test_all.py
+++ b/intrastat_base/tests/test_all.py
@@ -7,6 +7,15 @@ from .common import IntrastatCommon
 class TestIntrastatBase(IntrastatCommon):
     """Tests for this module"""
 
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.declaration_test_obj = cls.env["intrastat.declaration.test"]
+        cls._load_xml("intrastat_base", "tests/data/mail_template.xml")
+        cls.mail_template_id = (
+            "intrastat_base.base_intrastat_product_reminder_email_template"
+        )
+
     def test_company(self):
         # add 'Demo user' to intrastat_remind_user_ids
         self.demo_company.write(
diff --git a/intrastat_product/tests/__init__.py b/intrastat_product/tests/__init__.py
new file mode 100644
index 0000000..c8e439c
--- /dev/null
+++ b/intrastat_product/tests/__init__.py
@@ -0,0 +1,5 @@
+from . import common
+from . import common_sale
+from . import test_intrastat_product
+from . import test_company
+from . import test_sale_order
diff --git a/intrastat_product/tests/common.py b/intrastat_product/tests/common.py
new file mode 100644
index 0000000..77e350d
--- /dev/null
+++ b/intrastat_product/tests/common.py
@@ -0,0 +1,113 @@
+# Copyright 2021 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+from odoo.addons.intrastat_base.tests.common import IntrastatCommon
+
+
+class IntrastatProductCommon(IntrastatCommon):
+    @classmethod
+    def _init_products(cls):
+        # Create category - don't init intrastat values, do it in tests
+        vals = {
+            "name": "Robots",
+            "parent_id": cls.category_saleable.id,
+        }
+        cls.categ_robots = cls.category_obj.create(vals)
+
+        vals = {
+            "name": "C3PO",
+            "categ_id": cls.categ_robots.id,
+            "origin_country_id": cls.env.ref("base.us").id,
+            "weight": 300,
+            # Computer - C3PO is one of them
+            "hs_code_id": cls.hs_code_computer.id,
+        }
+        cls.product_c3po = cls.product_template_obj.create(vals)
+
+    @classmethod
+    def _init_company(cls):
+        # Default transport for company is Road
+        cls.demo_company.intrastat_transport_id = cls.transport_road
+
+    @classmethod
+    def _init_fiscal_position(cls):
+        vals = {
+            "name": "Intrastat Fiscal Position",
+            "intrastat": True,
+        }
+        cls.position = cls.position_obj.create(vals)
+
+    @classmethod
+    def _init_regions(cls):
+        # Create Belgium
+        cls._create_region()
+
+        vals = {
+            "code": "DE",
+            "name": "Germany",
+            "country_id": cls.env.ref("base.de").id,
+            "description": "Germany",
+        }
+        cls._create_region(vals)
+
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.region_obj = cls.env["intrastat.region"]
+        cls.transaction_obj = cls.env["intrastat.transaction"]
+        cls.transport_mode_obj = cls.env["intrastat.transport_mode"]
+        cls.partner_obj = cls.env["res.partner"]
+        cls.category_saleable = cls.env.ref("product.product_category_1")
+        cls.category_obj = cls.env["product.category"]
+        cls.product_template_obj = cls.env["product.template"]
+        cls.declaration_obj = cls.env["intrastat.product.declaration"]
+        cls.position_obj = cls.env["account.fiscal.position"]
+        cls.hs_code_computer = cls.env.ref("product_harmonized_system.84715000")
+
+        cls.transport_rail = cls.env.ref("intrastat_product.intrastat_transport_2")
+        cls.transport_road = cls.env.ref("intrastat_product.intrastat_transport_3")
+
+        cls._init_regions()
+        cls._init_company()
+        cls._init_fiscal_position()
+        cls._init_products()
+
+    @classmethod
+    def _create_region(cls, vals=None):
+        values = {
+            "code": "BE",
+            "country_id": cls.env.ref("base.be").id,
+            "company_id": cls.env.company.id,
+            "description": "Belgium",
+            "name": "Belgium",
+        }
+        if vals is not None:
+            values.update(vals)
+        cls.region = cls.region_obj.create(values)
+
+    @classmethod
+    def _create_transaction(cls, vals=None):
+        values = {
+            "code": "11",
+            "company_id": cls.env.company.id,
+            "description": "Sale / Purchase",
+        }
+        if vals is not None:
+            values.update(vals)
+        cls.transaction = cls.transaction_obj.create(values)
+
+    @classmethod
+    def _create_transport_mode(cls, vals=None):
+        values = {}
+        if vals is not None:
+            values.update(vals)
+        cls.transport_mode = cls.transport_mode_obj.create(values)
+
+    @classmethod
+    def _create_declaration(cls, vals=None):
+        values = {
+            "company_id": cls.env.company.id,
+        }
+        if vals is not None:
+            values.update(vals)
+        cls.declaration = cls.declaration_obj.create(values)
diff --git a/intrastat_product/tests/common_sale.py b/intrastat_product/tests/common_sale.py
new file mode 100644
index 0000000..9dc07ca
--- /dev/null
+++ b/intrastat_product/tests/common_sale.py
@@ -0,0 +1,43 @@
+# Copyright 2021 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from odoo.tests import Form
+
+from .common import IntrastatProductCommon
+
+
+class IntrastatSaleCommon(IntrastatProductCommon):
+    """
+    We define common flow:
+        - Customer in Netherlands
+    """
+
+    @classmethod
+    def _init_customer(cls, vals=None):
+        values = {
+            "name": "NL Customer",
+            "country_id": cls.env.ref("base.nl").id,
+            "property_account_position_id": cls.position.id,
+        }
+        if vals is not None:
+            values.update(vals)
+        cls.customer = cls.partner_obj.create(values)
+
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        cls.sale_obj = cls.env["sale.order"]
+        cls._init_customer()
+
+    @classmethod
+    def _create_sale_order(cls, vals=None):
+        vals = {
+            "partner_id": cls.customer.id,
+        }
+        sale_new = cls.sale_obj.new(vals)
+        sale_new.onchange_partner_id()
+        sale_vals = sale_new._convert_to_write(sale_new._cache)
+        cls.sale = cls.sale_obj.create(sale_vals)
+        with Form(cls.sale) as sale_form:
+            with sale_form.order_line.new() as line:
+                line.product_id = cls.product_c3po.product_variant_ids[0]
+                line.product_uom_qty = 3.0
diff --git a/intrastat_product/tests/test_company.py b/intrastat_product/tests/test_company.py
new file mode 100644
index 0000000..7fe99ac
--- /dev/null
+++ b/intrastat_product/tests/test_company.py
@@ -0,0 +1,40 @@
+# Copyright 2021 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from odoo.tests.common import SavepointCase
+
+from .common import IntrastatProductCommon
+
+
+class TestIntrastatCompany(IntrastatProductCommon):
+    """Tests for this module"""
+
+    def test_company_values(self):
+        # Exempt for arrivals and dispatches => exempt
+        self.demo_company.update(
+            {
+                "intrastat_arrivals": "exempt",
+                "intrastat_dispatches": "exempt",
+            }
+        )
+        self.assertEqual("exempt", self.demo_company.intrastat)
+
+        # Extended for arrivals or dispatches => extended
+        self.demo_company.update(
+            {
+                "intrastat_arrivals": "extended",
+            }
+        )
+        self.assertEqual("extended", self.demo_company.intrastat)
+
+        # standard for arrivals or dispatches => standard
+        self.demo_company.update(
+            {
+                "intrastat_arrivals": "exempt",
+                "intrastat_dispatches": "standard",
+            }
+        )
+        self.assertEqual("standard", self.demo_company.intrastat)
+
+
+class TestIntrastatProductCase(TestIntrastatCompany, SavepointCase):
+    """ Test Intrastat Product """
diff --git a/intrastat_product/tests/test_intrastat_product.py b/intrastat_product/tests/test_intrastat_product.py
new file mode 100644
index 0000000..0e30a7a
--- /dev/null
+++ b/intrastat_product/tests/test_intrastat_product.py
@@ -0,0 +1,34 @@
+# Copyright 2021 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from psycopg2 import IntegrityError
+
+from odoo.tests.common import SavepointCase
+from odoo.tools import mute_logger
+
+from .common import IntrastatProductCommon
+
+
+class TestIntrastatProduct(IntrastatProductCommon):
+    """Tests for this module"""
+
+    # Test duplicates
+    @mute_logger("odoo.sql_db")
+    def test_region(self):
+        with self.assertRaises(IntegrityError):
+            self._create_region()
+
+    @mute_logger("odoo.sql_db")
+    def test_transaction(self):
+        self._create_transaction()
+        with self.assertRaises(IntegrityError):
+            self._create_transaction()
+
+    @mute_logger("odoo.sql_db")
+    def test_transport_mode(self):
+        vals = {"code": 1, "name": "Sea"}
+        with self.assertRaises(IntegrityError):
+            self._create_transport_mode(vals)
+
+
+class TestIntrastatProductCase(TestIntrastatProduct, SavepointCase):
+    """ Test Intrastat Product """
diff --git a/intrastat_product/tests/test_sale_order.py b/intrastat_product/tests/test_sale_order.py
new file mode 100644
index 0000000..e3e6819
--- /dev/null
+++ b/intrastat_product/tests/test_sale_order.py
@@ -0,0 +1,92 @@
+# Copyright 2021 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+from freezegun import freeze_time
+
+from odoo.tests.common import SavepointCase
+
+from .common_sale import IntrastatSaleCommon
+
+
+class TestIntrastatProductSale(IntrastatSaleCommon):
+    """Tests for this module"""
+
+    def test_sale_to_invoice_default(self):
+        self._create_sale_order()
+        self.sale.action_confirm()
+        self.sale.picking_ids.action_assign()
+        for line in self.sale.picking_ids.move_line_ids:
+            line.qty_done = line.product_uom_qty
+        self.sale.picking_ids._action_done()
+        self.assertEqual("done", self.sale.picking_ids.state)
+
+        invoice = self.sale._create_invoices()
+        invoice.action_post()
+
+        # Check if transport mode has been transmitted to invoice
+        # It should be None as not defined on sale order
+        self.assertFalse(
+            invoice.intrastat_transport_id,
+        )
+
+    # Test specific transport set on sale to invoice
+    def test_sale_to_invoice(self):
+        self._create_sale_order()
+        # Set intrastat transport mode to rail
+        self.sale.intrastat_transport_id = self.transport_rail
+        self.sale.action_confirm()
+        self.sale.picking_ids.action_assign()
+        for line in self.sale.picking_ids.move_line_ids:
+            line.qty_done = line.product_uom_qty
+        self.sale.picking_ids._action_done()
+        self.assertEqual("done", self.sale.picking_ids.state)
+
+        invoice = self.sale._create_invoices()
+        invoice.action_post()
+
+        # Check if transport mode has been transmitted to invoice
+        self.assertEqual(
+            self.transport_rail,
+            invoice.intrastat_transport_id,
+        )
+
+    def test_sale_declaration(self):
+        date_order = "2021-09-01"
+        declaration_date = "2021-10-01"
+        with freeze_time(date_order):
+            self._create_sale_order()
+        # Set intrastat transport mode to rail
+        self.sale.intrastat_transport_id = self.transport_rail
+        self.sale.action_confirm()
+        self.sale.picking_ids.action_assign()
+        for line in self.sale.picking_ids.move_line_ids:
+            line.qty_done = line.product_uom_qty
+        self.sale.picking_ids._action_done()
+        self.assertEqual("done", self.sale.picking_ids.state)
+
+        with freeze_time(date_order):
+            invoice = self.sale._create_invoices()
+            invoice.action_post()
+
+        # Check if transport mode has been transmitted to invoice
+        self.assertEqual(
+            self.transport_rail,
+            invoice.intrastat_transport_id,
+        )
+        vals = {
+            "declaration_type": "dispatches",
+        }
+        with freeze_time(declaration_date):
+            self._create_declaration(vals)
+        self.declaration.action_gather()
+
+        expected_vals = {
+            "declaration_type": "dispatches",
+            "suppl_unit_qty": 3.0,
+            "hs_code_id": self.hs_code_computer,
+        }
+        line = self.declaration.computation_line_ids
+        self.assertDictContainsSubset(expected_vals, line)
+
+
+class TestIntrastatProductSaleCase(TestIntrastatProductSale, SavepointCase):
+    """ Test Intrastat Sale """
diff --git a/test-requirements.txt b/test-requirements.txt
index 4ad8e0e..864b829 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -1 +1,2 @@
 odoo-test-helper
+freezegun