Completed a 3 years in my present company - want to write a thank u letter to my boss & owner of this company

Dear All, I have Completed a 3 years in my present company.
I want to write a thank u letter to my boss & owner of this company. Can u plz suggest me some formats & matter for the same
regards

Hi,
What is the purpose behind the letter. Is it just to thank or to remind about any monetary hike. Instead of email whenever you get a opportunity to meet your Boss, express your happiness verbally, thank them for the opportunity, what you learned there etc.
If you are very keen on the letter please refer the following draft
Dear Sir or Respected Sir,
It is with immense pleasure I would like to share you that on_____ I have completed my three years of service with the Company!. Sir, I take this opportunity to thank you very much for the opportunity provided. I am very much enjoying my work and office work environment. Every day is a learning day for me. I am very much grateful to you that my tenure with this Company is helping me to enrich my knowledge every day.
I sincerely hope that my work contribution to upto your expectations. I look forward for further more long lasting rewarding career with _____________(name of the Company)
Thanking you,
Yours faithfully

A Hand-Written Thank You Note or Letter is nothing short of a Miracle to the Receiver. Try out
Harsh K Sharan
15.6.20

Hi Raju,

I am thinking in the line of VML. It's somewhat unusual for subordinates to write a Thanks letter or mail to HOD/Boss as routine. Ofcourse, meeting them or distributing sweets are ok., may be when got your increase or increment.

I have no clue what made you to write like this. Did you get an unique opportunity to learn certain thing or complete a project in record time/successfully, why do you think this is an extraordinary. Did it on completion of 1st & 2nd years?? Or Others also did the same think?? By raising these questions I'm not suggesting you can't do as proposed. Ofcourse it's good. But I only tried to understand why this?? anything special to highlight in this letter ?? when others are not doing like this (others shouldn't brand it as creasing). If you come out with little more info then it would serve the purpose better.

May be you can buy a nicely worded THANKS TO BOSS printed greeting card from the shops and hand over to him with sweets of his choice.

Hi!
I don't think there is any harm in writing a 'thank you' letter. We all know that there are different forms of communication. Written communication remains permanent in record and is deemed to be an official communication. Whereas, verbal communication is a temporary nature of communication which over the period loses its value and also get vanished with the exit of the 'Boss'/concerned officials. Further, written communication sometimes are more effective, if worded correctly, suitably and nicely.
However, I suggest the following contents:
Sir, at the outset, I am thankful to you for keeping faith in me and giving a chance to serve your esteemed Company. I have just completed three years of my working in the company and feel proud to be a member of the group.
Sir, the kind of opportunities I have been provided, I find myself professionally a better equipped person now. The guidance under your supervision has helped to convert myself into a different version of me whether it's on personal or professional front.
This Company has made all my professional ambition fulfilled. I am in fact contended to a greater extent in terms of everything.
Sir, I take this opportunity to sincerely express my gratitude to you and the company for all your help, support, cooperation and guidance to me. At the same time, I assure you for my best services at all times.
Thank you,
Sincere Regards,