Just simply

Dear Sir

I submit my resignation as of (todays date) giving one months notice. I will take any accrued holiday during the period of notice thus my final day will be ( date )

Signature

As per TJ’s example above. Keep it simple and to the point.

A resignation letter should be short and succinct, a “so long and thanks for everything” affair. If there are issues about current working practices, or specific reasons for the departure that need to be raised, it should be done during a leaving interview face to face with the appropriate person and if one is not offered, it should be requested. A resignation letter is not the place to start berating policies or processes.

As per TJ’s effort. The lack of ‘thanks for all the fish’ more than adequately displays any negative sentiment without actually having to write it.

A blank space is generally more troubling for an idiot manager than a real insult.

I wrote one the other week, it was one sentence long. So less sentences than this. Or possibly two, I’d have to go back and reread.

As per TJ states, keep it as simple as possible.

It’s a resignation letter, all you need in it is written intention to resign. Make sure the letter is dated and the date of your last day of work stated (if you can work it out).

Send a copy to your line manager and HR person (if there is one) or whoever deals with HR and keep a copy yourself.

There’s no need to thank people, or raise issues in it, all that’s needed is to say you are resigning so there’s proper formal written evidence of that fact.

They won’t have a moment of clarity after reading the letter and see everything from your point of view, you’ll just come across as bitter.

This. Keep it to the absolute professional minimum and move on.