[Name of contact person, if available]
[Title, if available]
[Customer Services Manager, if you don't have a contact name]
[Company Name]
[Company address 1]
[Company address 2]
[Company address 3]
[Postcode]
Re: [Account number, product, service etc]
Dear [Contact Person or Customer Service Manager],
On [date], I [bought, rented, had serviced etc] a [name of product with model number, service performed etc] at [location and other details of the transaction].
I am disappointed because your [product, service, billing etc.] has [not performed as it should, was wrong etc] because [state the problem as you understand it giving as much detail as possible].
To resolve the problem I would appreciate your [state the action you require e.g. refund, service performed again etc]. Enclosed is a copy/are copies of the [receipt, contract etc].
I look forward to hearing from you and to a resolution of this problem. I will wait for [set a time limit] before seeking help from [Trading Standards, consumer group, solicitor etc (details of relevant authorities can be found through our complaints procedures section]. Please contact me at the above address or by phone [give numbers].
Yours sincerely
[Sign]