My Top Five Tips For Letters of Complaint

1. Handwrite the letter.  This personal touch shows that you have taken the time to convey your grievance.
2. Find the name of the Chief Executive Officer or Chairman and address your letter to them.  You can usually Google this information. It is always best to aim at the top honcho.
3. Ideally you should find their home address, the impact is greater if you send your letter of complaint to their home.  Unfortunately in this day and age with more data protection regulation it is harder to find but Companies House is a good place to start.
4. Before you write your letter make a chronology so you know the order of events to provide the context to your grievance.
5. Keep a copy of your letter and send it Recorded Delivery.  This way you know someone has had to sign for it.

Good luck with your complaint!