diff --git a/shopinvader_anonymous_partner/models/res_partner.py b/shopinvader_anonymous_partner/models/res_partner.py
index 4400851144..4bebb32e25 100644
--- a/shopinvader_anonymous_partner/models/res_partner.py
+++ b/shopinvader_anonymous_partner/models/res_partner.py
@@ -3,6 +3,7 @@
 
 import secrets
 import typing
+from datetime import datetime
 
 from odoo import _, api, fields, models
 
@@ -16,6 +17,7 @@ def set_cookie(
         key: str,
         value: str,
         max_age: int,
+        expires: datetime | str | int,
         secure: bool,
         httponly: bool,
         samesite: typing.Literal["lax", "strict", "none"],
@@ -72,6 +74,18 @@ def _create_anonymous_partner__cookie(self, response: Response):
         )
         return partner
 
+    @api.model
+    def _delete_anonymous_partner__cookie(self, cookies: Cookies, response: Response):
+        """
+        Delete anonymous partner and cookie
+        """
+        self._get_anonymous_partner__cookie(cookies).unlink()
+        response.set_cookie(
+            key=COOKIE_NAME,
+            max_age=0,
+            expires=0,
+        )
+
     @api.model
     def _get_anonymous_partner__token(self, token: str):
         return (
diff --git a/shopinvader_anonymous_partner/tests/test_anonymous_partner.py b/shopinvader_anonymous_partner/tests/test_anonymous_partner.py
index b59b99f669..ddec37f24a 100644
--- a/shopinvader_anonymous_partner/tests/test_anonymous_partner.py
+++ b/shopinvader_anonymous_partner/tests/test_anonymous_partner.py
@@ -34,6 +34,14 @@ def anonymous_partner_get(self):
             return str(partner.id)
         return ""
 
+    @route("/test/anonymous_partner_delete", type="http", auth="none")
+    def anonymous_partner_delete(self):
+        request.env["res.partner"].with_user(
+            SUPERUSER_ID
+        )._delete_anonymous_partner__cookie(
+            request.httprequest.cookies, request.future_response
+        )
+
 
 class TestShopinvaderAnonymousPartner(TransactionCase):
     def test_create(self):
@@ -69,9 +77,19 @@ def test_get(self):
         )
         self.assertEqual(len(partner2), 0)
 
+    def test_delete(self):
+        partner = self.env["res.partner"]._create_anonymous_partner__cookie(
+            mock.MagicMock()
+        )
+        self.assertTrue(partner.exists())
+        self.env["res.partner"]._delete_anonymous_partner__cookie(
+            cookies={COOKIE_NAME: partner.anonymous_token}, response=mock.MagicMock()
+        )
+        self.assertFalse(partner.exists())
+
 
 class TestShopinvaderAnonymousPartnerEndToEnd(HttpCase):
-    def test_create_and_get(self):
+    def test_create_and_get_and_delete(self):
         resp = self.url_open("/test/anonymous_partner_create")
         resp.raise_for_status()
         token = resp.cookies.get(COOKIE_NAME)
@@ -89,3 +107,7 @@ def test_create_and_get(self):
         )
         resp.raise_for_status()
         self.assertEqual(int(resp.text), partner_id)
+        # delete cookie
+        resp = self.url_open("/test/anonymous_partner_delete")
+        resp.raise_for_status()
+        self.assertFalse(resp.cookies.get(COOKIE_NAME))
diff --git a/shopinvader_api_signin_jwt/README.rst b/shopinvader_api_signin_jwt/README.rst
index 3bf6f61b41..0127f41706 100644
--- a/shopinvader_api_signin_jwt/README.rst
+++ b/shopinvader_api_signin_jwt/README.rst
@@ -7,7 +7,7 @@ Shopinvader Api Signin JWT
    !! This file is generated by oca-gen-addon-readme !!
    !! changes will be overwritten.                   !!
    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-   !! source digest: sha256:75ace7db3bf1d327ad236aa12212ec10ad5363f81a8d3fd9896afe3f4d195fc4
+   !! source digest: sha256:335295feb8193e9691d56e3537300ec06022d9a6abe43a72a0639e1ce6e3fc68
    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
 
 .. |badge1| image:: https://img.shields.io/badge/maturity-Beta-yellow.png
@@ -24,6 +24,7 @@ Shopinvader Api Signin JWT
 
 This addon adds a web API to signin into the application and create a partner
 if the email in the jwt payload is unknown.
+If we had an anonymous partner, transfer his cart to the loggedin partner and delete it.
 
 **Table of contents**
 
@@ -33,7 +34,6 @@ if the email in the jwt payload is unknown.
 Known issues / Roadmap
 ======================
 
-* Manage anonymous cart (see https://github.com/shopinvader/odoo-shopinvader/issues/1428)
 * Use ``fastapi_auth_jwt.auth_jwt_authenticated_odoo_env`` dependency for the env (see https://github.com/OCA/rest-framework/issues/406)
 
 Bug Tracker
diff --git a/shopinvader_api_signin_jwt/__manifest__.py b/shopinvader_api_signin_jwt/__manifest__.py
index c84506a719..a51247e489 100644
--- a/shopinvader_api_signin_jwt/__manifest__.py
+++ b/shopinvader_api_signin_jwt/__manifest__.py
@@ -8,7 +8,11 @@
     "license": "AGPL-3",
     "author": "ACSONE SA/NV",
     "website": "https://github.com/shopinvader/odoo-shopinvader",
-    "depends": ["fastapi_auth_jwt"],
+    "depends": [
+        "fastapi_auth_jwt",
+        "shopinvader_anonymous_partner",
+        "shopinvader_sale_cart",
+    ],
     "data": [
         "security/res_groups.xml",
         "security/acl_res_partner.xml",
diff --git a/shopinvader_api_signin_jwt/readme/DESCRIPTION.rst b/shopinvader_api_signin_jwt/readme/DESCRIPTION.rst
index 9d807c0111..3c60d139e1 100644
--- a/shopinvader_api_signin_jwt/readme/DESCRIPTION.rst
+++ b/shopinvader_api_signin_jwt/readme/DESCRIPTION.rst
@@ -1,2 +1,3 @@
 This addon adds a web API to signin into the application and create a partner
 if the email in the jwt payload is unknown.
+If we had an anonymous partner, transfer his cart to the loggedin partner and delete it.
diff --git a/shopinvader_api_signin_jwt/readme/ROADMAP.rst b/shopinvader_api_signin_jwt/readme/ROADMAP.rst
index 945ce1163b..0bb1134142 100644
--- a/shopinvader_api_signin_jwt/readme/ROADMAP.rst
+++ b/shopinvader_api_signin_jwt/readme/ROADMAP.rst
@@ -1,2 +1 @@
-* Manage anonymous cart (see https://github.com/shopinvader/odoo-shopinvader/issues/1428)
 * Use ``fastapi_auth_jwt.auth_jwt_authenticated_odoo_env`` dependency for the env (see https://github.com/OCA/rest-framework/issues/406)
diff --git a/shopinvader_api_signin_jwt/routers/signin.py b/shopinvader_api_signin_jwt/routers/signin.py
index 0b9b688b40..723c8040a6 100644
--- a/shopinvader_api_signin_jwt/routers/signin.py
+++ b/shopinvader_api_signin_jwt/routers/signin.py
@@ -4,7 +4,7 @@
 import logging
 from typing import Annotated, Union
 
-from fastapi import APIRouter, Depends, Response, status
+from fastapi import APIRouter, Depends, Request, Response, status
 
 from odoo import api, models
 
@@ -28,17 +28,28 @@ def signin(
     partner: Annotated[Partner, Depends(auth_jwt_optionally_authenticated_partner)],
     payload: Annotated[Payload, Depends(auth_jwt_authenticated_payload)],
     response: Response,
+    request: Request,
 ) -> None:
     """
     Authenticate the partner based on a JWT token or a session cookie.
     Set the session cookie if allowed.
     Return HTTP code 201 if res.partner created (case of the first signin).
+    Transfer anonymous cart and delete anonymous partner if any.
     """
     if not partner:
-        env[
+        partner = env[
             "shopinvader_api_signin_jwt.signin_router.helper"
         ]._create_partner_from_payload(payload)
         response.status_code = status.HTTP_201_CREATED
+    anonymous_partner = env["res.partner"]._get_anonymous_partner__cookie(
+        request.cookies
+    )
+    if anonymous_partner:
+        anonymous_cart = env["sale.order"].sudo()._find_open_cart(anonymous_partner.id)
+        if anonymous_cart:
+            anonymous_cart._transfer_cart(partner.id)
+            anonymous_cart.unlink()
+        env["res.partner"]._delete_anonymous_partner__cookie(request.cookies, response)
 
 
 @signin_router.post("/signout")
diff --git a/shopinvader_api_signin_jwt/security/acl_res_partner.xml b/shopinvader_api_signin_jwt/security/acl_res_partner.xml
index 64f0f24fab..a41b91a5f8 100644
--- a/shopinvader_api_signin_jwt/security/acl_res_partner.xml
+++ b/shopinvader_api_signin_jwt/security/acl_res_partner.xml
@@ -9,7 +9,7 @@
         <field name="perm_read" eval="1" />
         <field name="perm_write" eval="1" />
         <field name="perm_create" eval="1" />
-        <field name="perm_unlink" eval="0" />
+        <field name="perm_unlink" eval="1" />
     </record>
 
 </odoo>
diff --git a/shopinvader_api_signin_jwt/static/description/index.html b/shopinvader_api_signin_jwt/static/description/index.html
index a5eb6e9e13..a478ab6d6d 100644
--- a/shopinvader_api_signin_jwt/static/description/index.html
+++ b/shopinvader_api_signin_jwt/static/description/index.html
@@ -367,11 +367,12 @@ <h1 class="title">Shopinvader Api Signin JWT</h1>
 !! This file is generated by oca-gen-addon-readme !!
 !! changes will be overwritten.                   !!
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-!! source digest: sha256:75ace7db3bf1d327ad236aa12212ec10ad5363f81a8d3fd9896afe3f4d195fc4
+!! source digest: sha256:335295feb8193e9691d56e3537300ec06022d9a6abe43a72a0639e1ce6e3fc68
 !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -->
 <p><a class="reference external image-reference" href="https://odoo-community.org/page/development-status"><img alt="Beta" src="https://img.shields.io/badge/maturity-Beta-yellow.png" /></a> <a class="reference external image-reference" href="http://www.gnu.org/licenses/agpl-3.0-standalone.html"><img alt="License: AGPL-3" src="https://img.shields.io/badge/licence-AGPL--3-blue.png" /></a> <a class="reference external image-reference" href="https://github.com/shopinvader/odoo-shopinvader/tree/16.0/shopinvader_api_signin_jwt"><img alt="shopinvader/odoo-shopinvader" src="https://img.shields.io/badge/github-shopinvader%2Fodoo--shopinvader-lightgray.png?logo=github" /></a></p>
 <p>This addon adds a web API to signin into the application and create a partner
-if the email in the jwt payload is unknown.</p>
+if the email in the jwt payload is unknown.
+If we had an anonymous partner, transfer his cart to the loggedin partner and delete it.</p>
 <p><strong>Table of contents</strong></p>
 <div class="contents local topic" id="contents">
 <ul class="simple">
@@ -388,7 +389,6 @@ <h1 class="title">Shopinvader Api Signin JWT</h1>
 <div class="section" id="known-issues-roadmap">
 <h1><a class="toc-backref" href="#toc-entry-1">Known issues / Roadmap</a></h1>
 <ul class="simple">
-<li>Manage anonymous cart (see <a class="reference external" href="https://github.com/shopinvader/odoo-shopinvader/issues/1428">https://github.com/shopinvader/odoo-shopinvader/issues/1428</a>)</li>
 <li>Use <tt class="docutils literal">fastapi_auth_jwt.auth_jwt_authenticated_odoo_env</tt> dependency for the env (see <a class="reference external" href="https://github.com/OCA/rest-framework/issues/406">https://github.com/OCA/rest-framework/issues/406</a>)</li>
 </ul>
 </div>
diff --git a/shopinvader_api_signin_jwt/tests/test_signin.py b/shopinvader_api_signin_jwt/tests/test_signin.py
index 3243e0283c..39ffa4ebbe 100644
--- a/shopinvader_api_signin_jwt/tests/test_signin.py
+++ b/shopinvader_api_signin_jwt/tests/test_signin.py
@@ -7,6 +7,7 @@
 
 from odoo.addons.fastapi.tests.common import FastAPITransactionCase
 from odoo.addons.fastapi_auth_jwt.dependencies import auth_jwt_default_validator_name
+from odoo.addons.shopinvader_anonymous_partner.models.res_partner import COOKIE_NAME
 
 from ..routers import signin_router
 
@@ -79,6 +80,38 @@ def test_signin(self):
             res = client.post("/signin", headers={"Authorization": token})
         self.assertEqual(res.status_code, 200)
 
+    def test_signin_anonymous_cart(self):
+        anonymous_partner = self.env["res.partner"].create(
+            {"name": "Test anonymous", "anonymous_token": "1234", "active": False}
+        )
+        product = self.env["product.product"].create(
+            {"name": "product", "uom_id": self.env.ref("uom.product_uom_unit").id}
+        )
+        anonymous_cart = self.env["sale.order"].create(
+            {
+                "partner_id": anonymous_partner.id,
+                "order_line": [
+                    (0, 0, {"product_id": product.id, "product_uom_qty": 1}),
+                ],
+                "typology": "cart",
+            }
+        )
+
+        token = self._get_token()
+        with self._create_test_client() as client:
+            res = client.post(
+                "/signin",
+                headers={"Authorization": token},
+                cookies={COOKIE_NAME: "1234"},
+            )
+        self.assertFalse(res.cookies.get(COOKIE_NAME))
+        self.assertFalse(anonymous_partner.exists())
+        self.assertFalse(anonymous_cart.exists())
+        partner = self.env["res.partner"].search([("email", "=", "test@mail.com")])
+        cart = self.env["sale.order"].search([("partner_id", "=", partner.id)])
+        self.assertEqual(len(cart.order_line), 1)
+        self.assertEqual(cart.order_line[0].product_id, product)
+
     def test_signout(self):
         self.validator.write({"cookie_enabled": True, "cookie_name": "test_cookie"})
         token = self._get_token()
diff --git a/shopinvader_sale_cart/models/sale_order.py b/shopinvader_sale_cart/models/sale_order.py
index 327d96596d..69208b4067 100644
--- a/shopinvader_sale_cart/models/sale_order.py
+++ b/shopinvader_sale_cart/models/sale_order.py
@@ -83,3 +83,39 @@ def _get_cart_line(self, product_id):
         return self.order_line.filtered(
             lambda l, product_id=product_id: l.product_id.id == product_id
         )[:1]
+
+    def _update_cart_lines_from_cart(self, cart):
+        self.ensure_one()
+        update_cmds = []
+        for cart_line in cart.order_line:
+            line = self._get_cart_line(cart_line.product_id.id)
+            if line:
+                new_qty = line.product_uom_qty + cart_line.product_uom_qty
+                vals = {"product_uom_qty": new_qty}
+                vals.update(line._play_onchanges_cart_line(vals))
+                cmd = (1, line.id, vals)
+            else:
+                vals = {
+                    "order_id": self.id,
+                    "product_id": cart_line.product_id.id,
+                    "product_uom_qty": cart_line.product_uom_qty,
+                }
+                vals.update(self.env["sale.order.line"]._play_onchanges_cart_line(vals))
+                cmd = (0, None, vals)
+            update_cmds.append(cmd)
+        self.write({"order_line": update_cmds})
+
+    def _transfer_cart(self, partner_id):
+        """
+        Copy the lines of this cart to the current cart of a given partner.
+        Merge lines of identical products.
+        If the partner does not have a current cart yet, create one.
+        This cart is not deleted.
+        It is the responsibility of the caller to remove it if desired.
+        """
+        self.ensure_one()
+        cart = self._find_open_cart(partner_id)
+        if not cart:
+            cart = self._create_empty_cart(partner_id)
+        cart._update_cart_lines_from_cart(self)
+        return cart
diff --git a/shopinvader_sale_cart/tests/__init__.py b/shopinvader_sale_cart/tests/__init__.py
new file mode 100644
index 0000000000..7388d2baaa
--- /dev/null
+++ b/shopinvader_sale_cart/tests/__init__.py
@@ -0,0 +1 @@
+from . import test_sale_cart
diff --git a/shopinvader_sale_cart/tests/test_sale_cart.py b/shopinvader_sale_cart/tests/test_sale_cart.py
new file mode 100644
index 0000000000..a7b2aec1f8
--- /dev/null
+++ b/shopinvader_sale_cart/tests/test_sale_cart.py
@@ -0,0 +1,37 @@
+# Copyright 2024 ACSONE SA/NV
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl).
+
+from odoo.addons.sale_cart.tests.test_sale_cart import TestSaleCart as TestSaleCartBase
+
+
+class TestSaleCart(TestSaleCartBase):
+    def test_transfer_cart(self):
+        product_2 = self.env["product.product"].create(
+            {"name": "product", "uom_id": self.env.ref("uom.product_uom_unit").id}
+        )
+        partner_2 = self.env["res.partner"].create({"name": "partner 2"})
+        so_cart_2 = self.env["sale.order"].create(
+            {
+                "partner_id": partner_2.id,
+                "order_line": [
+                    (0, 0, {"product_id": self.product.id, "product_uom_qty": 1}),
+                    (0, 0, {"product_id": product_2.id, "product_uom_qty": 1}),
+                ],
+                "typology": "cart",
+            }
+        )
+        merged_cart = so_cart_2._transfer_cart(self.partner.id)
+        self.assertEqual(merged_cart.id, self.so_cart.id)
+        self.assertEqual(len(merged_cart.order_line), 2)
+        self.assertEqual(
+            merged_cart.order_line.filtered(
+                lambda l, product=self.product: l.product_id.id == product.id
+            ).product_uom_qty,
+            2,
+        )
+        self.assertEqual(
+            merged_cart.order_line.filtered(
+                lambda l, product=product_2: l.product_id.id == product.id
+            ).product_uom_qty,
+            1,
+        )