Pls help to ask for a formally letter for bank use

Actually you really don't have to write such letter to the bank to write off the visa annual fee. I just phoned the credit card customer service hotline and made the request, usually they would do so. However, if you still want to write such letter, it is as follows : -

Dear Sir / Madam

Re : Credit Card No. xxxx-xxxx-xxxx-xxx

With reference to the captioned credit card, I would like to enquire whether you would waive the annual fee for the coming year in consideration of my past good record and my continuation of the use of your credit card.

I look forward to receiving your prompt reply and thank you for your kind attention in this matter.

Yours faithfully

Date: xxxxxxxxxxxx

Dear Sir/ Madam,
I am writing this letter to request your consideration in waiving my Visa annual fee for this year.

Here is some information you need:
Name : Chan Tai Man
ID # : xxxxxx (x)
Billing address: xxxxxxxxx

I appreciate the service of your bank, however, consider other banks offering the same service without the annual fee, i still would like to keep your card based on zero annual fee.

Your attention is highly appreciated in advance!

Best Regards,
Chan Tai Man