Can I Say No to Overtime During My Notice Period? And shift the responsibility on Manager?

Weighing Risks and Consequences

In any kind of decision making like this you have to weigh the worst possible thing that could happen and the chance of it happening. So if you decide not do this overtime and politely inform management that you will not be doing it, the question becomes: How can management retaliate against you, what is the worst thing they could do to you, and what is the chance they will do so?

For example if they can withhold or delay giving you your relieving letter and thus mess up the start date of your new job, is the time and stress dealing with that worse than the time and stress of doing the unpaid overtime?

Random strangers on the internet cannot answer these questions for you, since we do not know what your aversion is to doing the overtime vs your stamina for dealing with a retaliatory company. If you have mentors or people you look up to who can give you wise counsel they may provide an idea or approach unique to your situation, or be willing to offer direct help that changes the risk formula.

I've always held the firm belief that we are supposed to work the hours we are paid for. If I work overtime I am to be compensated for it otherwise it is essentially a pay cut for me as I get the same amount of money but have more hours.

So I personally would work the hours initially agreed upon in your contract and clock out when the time is up (given that you do good work in those hours).

If your company compensates you for the overtime then it's up to your own discretion and enthusiasm if you want to see the project progress even further then it normally would.

Now, the downside of just not doing the overtime is that it might reflect in your employment reference (or whatever the Indian equivalent is called).

I personally would seek a direct conversation with your manager to adress the topic and present him with the problem at hand and available solutions and go from there.

TLDR: Don't do the overtime, except when you really feel like it or get good compensation. But more importantly. Talk to your manager directly about the problem and look for a solution that you both agree upon.