My aunt is Medicaid pending. Should a hefty refund check be deposited in her account?

This is her income, and she does have it. There is no reason that it has to be deposited until her medicaid is approved. You can then assess where her accounting is, if she has the ability to use this for personal needs and purchases, or if she is over the limit and must apply it to costs. You can await approval on the basis of where her assets are now; I say this only because of my fear that throwing a check for 900 in may throw a monkey wrench into the machinery and hurt the entire process which is nearly finished. You are, I am assuming, her POA and handling her finances????? Await her approval. See that her accounting is set up and running, and then call medicaid to inform them of this check you will be depositing and ask them for their advice. would be my advice. She is allowed a certain amount in her spending account. When she has purchased with that money you can put this check in and she will have purchasing power again, I would assume. Checks are usually good for a certain amount of time, often years. You can check on that with a bank. I understand you are not attempting to hide assets, only attempting not to mess up paperwork and application mid process and ruining her entire application. I hope others have more advice for you.