diff --git a/setup/website_contact_lastname/odoo/addons/website_contact_lastname b/setup/website_contact_lastname/odoo/addons/website_contact_lastname
new file mode 120000
index 0000000000..c444f62428
--- /dev/null
+++ b/setup/website_contact_lastname/odoo/addons/website_contact_lastname
@@ -0,0 +1 @@
+../../../../website_contact_lastname
\ No newline at end of file
diff --git a/setup/website_contact_lastname/setup.py b/setup/website_contact_lastname/setup.py
new file mode 100644
index 0000000000..28c57bb640
--- /dev/null
+++ b/setup/website_contact_lastname/setup.py
@@ -0,0 +1,6 @@
+import setuptools
+
+setuptools.setup(
+    setup_requires=['setuptools-odoo'],
+    odoo_addon=True,
+)
diff --git a/website_sale_partner_firstname/__init__.py b/website_sale_partner_firstname/__init__.py
new file mode 100644
index 0000000000..ea6bb1f80b
--- /dev/null
+++ b/website_sale_partner_firstname/__init__.py
@@ -0,0 +1,5 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from . import controllers
+from . import models
diff --git a/website_sale_partner_firstname/__manifest__.py b/website_sale_partner_firstname/__manifest__.py
new file mode 100644
index 0000000000..0f9730ac00
--- /dev/null
+++ b/website_sale_partner_firstname/__manifest__.py
@@ -0,0 +1,22 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+{
+    "name": "Website Contact Lastname",
+    "version": "15.0.1.0.0",
+    "category": "Website",
+    "website": "https://github.com/OCA/website",
+    "author": "Sygel Technology," "Odoo Community Association (OCA)",
+    "license": "AGPL-3",
+    "application": False,
+    "installable": True,
+    "depends": [
+        "website_account_fiscal_position_partner_type",
+        "partner_firstname",
+    ],
+    "data": [
+        "views/templates.xml",
+        "views/auth_signup_login_templates.xml",
+        "views/portal_templates.xml",
+    ],
+}
diff --git a/website_sale_partner_firstname/controllers/__init__.py b/website_sale_partner_firstname/controllers/__init__.py
new file mode 100644
index 0000000000..294141a404
--- /dev/null
+++ b/website_sale_partner_firstname/controllers/__init__.py
@@ -0,0 +1,5 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from . import main
+from . import portal
diff --git a/website_sale_partner_firstname/controllers/main.py b/website_sale_partner_firstname/controllers/main.py
new file mode 100644
index 0000000000..ab0cdb9f37
--- /dev/null
+++ b/website_sale_partner_firstname/controllers/main.py
@@ -0,0 +1,159 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from odoo import _
+from odoo.http import request
+
+from odoo.addons.auth_signup.controllers.main import AuthSignupHome
+from odoo.addons.website_sale.controllers.main import WebsiteSale
+
+
+class WebsiteSale(WebsiteSale):
+    def _get_mandatory_fields_shipping(self, country_id=False):
+        req = super()._get_mandatory_fields_shipping(country_id)
+        req += ["firstname"]
+        if "name" in req:
+            req.remove("name")
+        return req
+
+    def _get_mandatory_fields_billing(self, country_id=False):
+        req = super()._get_mandatory_fields_billing(country_id)
+        req.append("firstname")
+        if request.env.context.get("fiscal_position_type") == "b2c":
+            req.append("lastname")
+        # Name is removed as this field cannot be explicitly edited
+        # It is edited in the backend through the fields first name
+        # and lastname
+        if "name" in req:
+            req.remove("name")
+        return req
+
+    def values_postprocess(self, order, mode, values, errors, error_msg):
+        new_values, errors, error_msg = super(WebsiteSale, self).values_postprocess(
+            order=order, mode=mode, values=values, errors=errors, error_msg=error_msg
+        )
+        new_values.update(
+            {
+                "firstname": values.get("firstname") or "",
+                "lastname": values.get("lastname") or "",
+            }
+        )
+        # Name is removed as this field cannot be explicitly edited
+        # It is edited in the backend through the fields first name
+        # and lastname
+        new_values.pop("name")
+        return new_values, errors, error_msg
+
+    def checkout_form_validate(self, mode, all_form_values, data):
+        required_fields = [
+            f for f in (all_form_values.get("field_required") or "").split(",") if f
+        ]
+        # Name is removed as this field cannot be explicitly edited
+        # It is edited in the backend through the fields first name
+        # and lastname
+        if "name" in required_fields:
+            required_fields.remove("name")
+        all_form_values["field_required"] = ",".join(required_fields)
+        error, error_message = super().checkout_form_validate(
+            mode, all_form_values, data
+        )
+        if data.get("partner_id"):
+            partner_su = (
+                request.env["res.partner"]
+                .sudo()
+                .browse(int(data["partner_id"]))
+                .exists()
+            )
+            can_edit_vat = (
+                partner_su.parent_id.can_edit_vat()
+                if partner_su.parent_id
+                else partner_su.can_edit_vat()
+            )
+            firstname_change = (
+                partner_su
+                and "firstname" in data
+                and data["firstname"] != partner_su.firstname
+            )
+            if firstname_change and not can_edit_vat:
+                error["firstname"] = "error"
+                error_message.append(
+                    _(
+                        "Changing your name is not allowed once invoices have been"
+                        " issued for your account. Please contact us directly for "
+                        "this operation."
+                    )
+                )
+            # When lastname field in form is empty, its values is False
+            # When lastname field in backend is empty, its values is ''
+            # In that case, if both are compared, they are considered to be
+            # different so data['lastname'] != partner_su.lastname would
+            # return True although no real change would have been applied.
+            lastname_change = (
+                partner_su
+                and "lastname" in data
+                and data["lastname"] != partner_su.lastname
+                and (data["lastname"] or partner_su.lastname not in ["", False])
+            )
+            if lastname_change and not can_edit_vat:
+                error["lastname"] = "error"
+                error_message.append(
+                    _(
+                        "Changing your last name is not allowed once invoices have"
+                        " been issued for your account. Please contact us directly"
+                        " for this operation."
+                    )
+                )
+
+            # Prevent change the partner name, lastname if
+            # it is an internal user.
+            if (firstname_change or lastname_change) and not all(
+                partner_su.user_ids.mapped("share")
+            ):
+                error.update(
+                    {
+                        "firstname": "error" if firstname_change else None,
+                        "lastname": "error" if lastname_change else None,
+                    }
+                )
+                error_message.append(
+                    _(
+                        "If you are ordering for an external person, please place "
+                        "your order via the backend. If you wish to change your "
+                        "name or last name, please do so in the account settings "
+                        "or contact your administrator."
+                    )
+                )
+        return error, error_message
+
+
+class AuthSignupHome(AuthSignupHome):
+    def get_auth_signup_qcontext(self):
+        qcontext = super().get_auth_signup_qcontext()
+        qcontext.update(
+            {
+                k: v
+                for (k, v) in request.params.items()
+                if k
+                in {
+                    "lastname",
+                }
+            }
+        )
+        if "name" in qcontext:
+            qcontext["firstname"] = qcontext["name"]
+        if (
+            "error" not in qcontext
+            and request.httprequest.method == "POST"
+            and qcontext.get("fiscal_position_type") == "b2c"
+            and not qcontext.get("lastname")
+        ):
+            qcontext["error"] = _("Lastname is required for B2C users.")
+        return qcontext
+
+    def _prepare_signup_values(self, qcontext):
+        values = super()._prepare_signup_values(qcontext)
+        if "firstname" in qcontext:
+            values["firstname"] = qcontext["firstname"]
+        if "lastname" in qcontext:
+            values["lastname"] = qcontext["lastname"]
+        return values
diff --git a/website_sale_partner_firstname/controllers/portal.py b/website_sale_partner_firstname/controllers/portal.py
new file mode 100644
index 0000000000..e99afd139f
--- /dev/null
+++ b/website_sale_partner_firstname/controllers/portal.py
@@ -0,0 +1,63 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from odoo import _
+from odoo.http import request
+
+from odoo.addons.portal.controllers.portal import CustomerPortal
+
+
+class CustomerPortal(CustomerPortal):
+
+    CustomerPortal.OPTIONAL_BILLING_FIELDS += [
+        "firstname",
+        "lastname",
+    ]
+
+    def details_form_validate(self, data):
+        context = dict(request.env.context)
+        # 'name' field cannont be updated as it would recompute fields
+        # firstname and lastname. That is why it is set in context
+        # that changes in field name need to be ignored.
+        context.update({"name_ignore": True})
+        request.env.context = context
+        error, error_message = super().details_form_validate(data)
+        partner = request.env.user.partner_id
+        if partner.can_edit_vat():
+            if "firstname" in data and not data.get("Name"):
+                error["firstname"] = "error"
+                error_message.append(_("Firstname is mandatory."))
+            if (
+                "lastname" in data
+                and not data.get("lastname")
+                and (
+                    (data.get("fiscal_position_type") == "b2c")
+                    or (
+                        partner.fiscal_position_type == "b2c"
+                        and not data.get("fiscal_position_type") == "b2b"
+                    )
+                )
+            ):
+                error["lastname"] = "error"
+                error["fiscal_position_type"] = "error"
+                error_message.append(_("Lastname is mandatory for B2C users."))
+        else:
+            if "firstname" in data and data.get("firstname") != partner.firstname:
+                error["firstname"] = "error"
+                error_message.append(
+                    _(
+                        "Changing Name is not allowed once document(s) have been "
+                        "issued for your account. Please contact us directly for "
+                        "this operation."
+                    )
+                )
+            if "lastname" in data and data.get("lastname") != partner.lastname:
+                error["lastname"] = "error"
+                error_message.append(
+                    _(
+                        "Changing Lastname is not allowed once document(s) have "
+                        "been issued for your account. Please contact us directly "
+                        "for this operation."
+                    )
+                )
+        return error, error_message
diff --git a/website_sale_partner_firstname/models/__init__.py b/website_sale_partner_firstname/models/__init__.py
new file mode 100644
index 0000000000..a227d7676d
--- /dev/null
+++ b/website_sale_partner_firstname/models/__init__.py
@@ -0,0 +1,5 @@
+# Copyright 2023 Manuel Regidor <manuelregidor@sygel.es>
+# License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+
+from . import res_users
+from . import res_partner
diff --git a/website_sale_partner_firstname/models/res_partner.py b/website_sale_partner_firstname/models/res_partner.py
new file mode 100644
index 0000000000..943a233393
--- /dev/null
+++ b/website_sale_partner_firstname/models/res_partner.py
@@ -0,0 +1,26 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl-3).
+
+from odoo import api, models
+from odoo.http import request
+
+
+class Partner(models.Model):
+    _inherit = "res.partner"
+
+    @api.model
+    def signup_retrieve_info(self, token):
+        res = super().signup_retrieve_info(token)
+        partner = self._signup_retrieve_partner(token, raise_exception=True)
+        res.update(
+            {
+                "name": partner.firstname,
+                "lastname": partner.lastname,
+            }
+        )
+        return res
+
+    def write(self, vals):
+        if vals.get("name") and request.env.context.get("name_ignore"):
+            vals.pop("name")
+        return super().write(vals)
diff --git a/website_sale_partner_firstname/models/res_users.py b/website_sale_partner_firstname/models/res_users.py
new file mode 100644
index 0000000000..01138a8976
--- /dev/null
+++ b/website_sale_partner_firstname/models/res_users.py
@@ -0,0 +1,37 @@
+# Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+# License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl-3).
+
+from odoo import api, models
+
+
+class ResUsers(models.Model):
+    _inherit = "res.users"
+
+    @api.model
+    def signup(self, values, token=None):
+        if token:
+            partner = self.env["res.partner"]._signup_retrieve_partner(
+                token, check_validity=True, raise_exception=True
+            )
+            partner_user = partner.user_ids and partner.user_ids[0] or False
+            # Don't update firstname and lastname if partner
+            # related to user exists (i.e. when resetting password)
+            if partner_user:
+                values.pop("firstname", None)
+                values.pop("lastname", None)
+        return super().signup(values, token)
+
+    def _create_user_from_template(self, values):
+        user = super()._create_user_from_template(values)
+        # Because of the way the name is computed, it is important to
+        # reset the values so the final name is correct.
+        # It cannot be done before (the way would be setting the value of name
+        # if param. values to '') as the funcion _create_user_from_template
+        # checks that values contains a value for 'name'
+        user.write(
+            {
+                "firstname": values.get("firstname"),
+                "lastname": values.get("lastname"),
+            }
+        )
+        return user
diff --git a/website_sale_partner_firstname/readme/CONFIGURE.rst b/website_sale_partner_firstname/readme/CONFIGURE.rst
new file mode 100644
index 0000000000..05dcf8709a
--- /dev/null
+++ b/website_sale_partner_firstname/readme/CONFIGURE.rst
@@ -0,0 +1 @@
+No configuration needed.
diff --git a/website_sale_partner_firstname/readme/CONTRIBUTORS.rst b/website_sale_partner_firstname/readme/CONTRIBUTORS.rst
new file mode 100644
index 0000000000..9a9de12727
--- /dev/null
+++ b/website_sale_partner_firstname/readme/CONTRIBUTORS.rst
@@ -0,0 +1,3 @@
+* `Sygel <https://www.sygel.es>`_:
+
+  * Manuel Regidor
diff --git a/website_sale_partner_firstname/readme/DESCRIPTION.rst b/website_sale_partner_firstname/readme/DESCRIPTION.rst
new file mode 100644
index 0000000000..f77181f0df
--- /dev/null
+++ b/website_sale_partner_firstname/readme/DESCRIPTION.rst
@@ -0,0 +1,2 @@
+This module allows users to introduce and edit their lastname
+from the portal.
diff --git a/website_sale_partner_firstname/readme/USAGE.rst b/website_sale_partner_firstname/readme/USAGE.rst
new file mode 100644
index 0000000000..995cc089f7
--- /dev/null
+++ b/website_sale_partner_firstname/readme/USAGE.rst
@@ -0,0 +1,8 @@
+Lastname can be set from 3 differents places in the portal:
+
+* Signup page
+* User's details page
+* Checkout billing address page
+* Checkout shipping address page
+
+In all cases but the checkout shipping address page, lastname field must be filled if the user is B2C. Otherwise, it can be left blank. In the checkout shipping address page, lastname can be left blank.
diff --git a/website_sale_partner_firstname/static/description/icon.png b/website_sale_partner_firstname/static/description/icon.png
new file mode 100644
index 0000000000..3a0328b516
Binary files /dev/null and b/website_sale_partner_firstname/static/description/icon.png differ
diff --git a/website_sale_partner_firstname/views/auth_signup_login_templates.xml b/website_sale_partner_firstname/views/auth_signup_login_templates.xml
new file mode 100644
index 0000000000..24da1d08d6
--- /dev/null
+++ b/website_sale_partner_firstname/views/auth_signup_login_templates.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!--
+    Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+    License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+-->
+<odoo>
+    <template id="website_contact_lastname_auth_signup" inherit_id="auth_signup.fields">
+        <xpath expr="//div[hasclass('field-name')]" position="after">
+            <div class="form-group field-lastname">
+                <label for="name">Last Name</label>
+                <input
+                    type="text"
+                    name="lastname"
+                    t-att-value="lastname"
+                    id="lastname"
+                    class="form-control form-control-sm"
+                    t-att-readonly="'readonly' if only_passwords else None"
+                    t-att-autofocus="'autofocus' if login and not only_passwords else None"
+                />
+            </div>
+        </xpath>
+    </template>
+</odoo>
diff --git a/website_sale_partner_firstname/views/portal_templates.xml b/website_sale_partner_firstname/views/portal_templates.xml
new file mode 100644
index 0000000000..26566f8654
--- /dev/null
+++ b/website_sale_partner_firstname/views/portal_templates.xml
@@ -0,0 +1,42 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!--
+    Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+    License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+-->
+<odoo>
+    <template
+        id="website_contact_lastname_portal_my_details"
+        inherit_id="portal.portal_my_details"
+    >
+        <xpath expr="//label[@for='name']/.." position="after">
+            <div
+                t-attf-class="form-group #{error.get('firstname') and 'o_has_error' or ''} col-xl-6"
+            >
+                <label class="col-form-label" for="firstname">Name</label>
+                <input
+                    type="text"
+                    name="firstname"
+                    t-attf-class="form-control #{error.get('firstname') and 'is-invalid' or ''}"
+                    t-att-disabled="None if partner_can_edit_vat else '1'"
+                    t-att-value="firstname or partner.firstname"
+                />
+            </div>
+            <div
+                t-attf-class="form-group #{error.get('lastname') and 'o_has_error' or ''} col-xl-6"
+            >
+                <label class="col-form-label" for="lastname">Lastname</label>
+                <input
+                    type="text"
+                    name="lastname"
+                    t-attf-class="form-control #{error.get('lastname') and 'is-invalid' or ''}"
+                    t-att-disabled="None if partner_can_edit_vat else '1'"
+                    t-att-value="lastname or partner.lastname"
+                />
+            </div>
+        </xpath>
+        <!-- Name field is removed as it is computed from firstname and lastname -->
+        <xpath expr="//label[@for='name']/.." position="attributes">
+            <attribute name="style">display: none;</attribute>
+        </xpath>
+    </template>
+</odoo>
diff --git a/website_sale_partner_firstname/views/templates.xml b/website_sale_partner_firstname/views/templates.xml
new file mode 100644
index 0000000000..f56ab28416
--- /dev/null
+++ b/website_sale_partner_firstname/views/templates.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!--
+    Copyright 2023 Manuel Regidor <manuel.regidor@sygel.es>
+    License AGPL-3.0 or later (http://www.gnu.org/licenses/agpl.html).
+-->
+<odoo>
+    <template id="website_contact_lastname_address" inherit_id="website_sale.address">
+        <xpath expr="//input[@name='name']/.." position="after">
+            <t
+                t-set='name_no_edit'
+                t-value="(mode == ('edit', 'billing') and 'vat' in checkout and checkout['vat'] and not can_edit_vat and mode) or (mode == ('edit', 'shipping') and 'parent_id' in checkout and checkout['parent_id'] and not checkout['parent_id'].can_edit_vat())"
+            />
+            <div
+                t-attf-class="form-group #{error.get('firstname') and 'o_has_error' or ''} col-lg-12 div_firstname"
+            >
+                <label class="col-form-label" for="name">Name</label>
+                <input
+                    type="text"
+                    name="firstname"
+                    t-attf-class="form-control #{error.get('firstname') and 'is-invalid' or ''}"
+                    t-att-value="'firstname' in checkout and checkout['firstname']"
+                    t-att-readonly="'1' if name_no_edit else None"
+                />
+            </div>
+            <div
+                t-attf-class="form-group #{error.get('lastname') and 'o_has_error' or ''} col-lg-6 div_lastname"
+            >
+                <label class="col-form-label" for="name">Lastname</label>
+                <input
+                    type="text"
+                    name="lastname"
+                    t-attf-class="form-control #{error.get('lastname') and 'is-invalid' or ''}"
+                    t-att-value="'lastname' in checkout and checkout['lastname']"
+                    t-att-readonly="'1' if name_no_edit else None"
+                />
+            </div>
+        </xpath>
+        <!-- Name field is removed as it is computed from firstname and lastname -->
+        <xpath expr="//input[@name='name']/.." position="attributes">
+            <attribute name="style">display: none;</attribute>
+        </xpath>
+    </template>
+</odoo>