Hi,

By default, portal users in Odoo only have access to the customer portal (documents, quotations, invoices, tasks, etc.). The Time Off (hr_holidays) app is restricted to internal users (employees). That’s why portal users cannot see/request holidays directly.

To request holidays, a user must be an Employee in Odoo, which means:

    The user’s record (res.users) is linked to an employee (hr.employee).

    The user has the group Time Off / Employee (hr_holidays.group_hr_holidays_user).

But this also makes them an Internal User (not a Portal User). Portal users do not have access to HR menus.

Recommendation:-

If these are employees → make them Internal Users with the Time Off / Employee group. (Official supported way).

If they are external collaborators/partners and you don’t want to buy licenses → you need a custom portal extension to expose holiday request forms.

So,

Portal users cannot access the Time Off app by default. To let them request holidays, you must either:

    Upgrade them to Internal Users with the “Time Off / Employee” group (official way, requires license), or

    Develop/Install a custom portal module that exposes holiday request forms to portal users.

Hope it helps