How do I politely decline a research grant?
How do I politely decline a research grant?


Let's be clear here. Based on your account I'm getting the impression that, with a reasonably high level of confidence, there is no way for you to "politely" decline the grant. The very action of declining will reflect poorly on you and show you to be an unreliable and difficult to work with person, and is likely to upset your PI and the funding agency who went to the trouble to evaluate your application. So, it's not about the "how". It's the action of declining that is by its nature impolite.

You may feel this is unfair. You may feel that you were given inaccurate information at the time of submitting the grant that led you to make a decision you now regret. You may very well be right on both of those points. In an ideal world you would simply explain what happened and everyone would agree that it makes sense for you to decline the grant. However, in the world we actually live in, I'd say accept it, do the work, use it as a learning experience and move on. And congratulations for getting the grant, it obviously says good things about you and if you do a good job has potential to benefit you in the future in many ways other than the measly stipend.