Hi bethhall0,
Anything posted or couriered to you from another country goes through customs to check it is not banned or restricted and you pay the right tax and ‘duty’ on it.
The parcel or courier company (for example, Royal Mail or Parcelforce) is responsible for taking goods through UK customs.
You do not pay customs charges if imported goods are under the personal allowance, please see below link for more information.
Tax and customs for goods sent from abroad
If imported goods are personal belongings returning back to UK, you can send a request for a repayment.
How to claim a repayment of import duty and VAT if you've overpaid
Report incorrect Customs Duty or VAT on items imported by post (BOR286)z
Thank you.