He died on June 18, 2018. SS check direct deposited on June 20, 2018. Can I keep it?

Also, SSI checks are not prorated for the partial month he lived.

The SSI check that was deposited on June 20, 2018 is for the month of may. Social Security holds back a month when you first start to collect. The June 2018 SSI check would have come out on July 20, 2018. Since funeral homes generally report the death of a deceased immediately, I doubt June's payment will be deposited in July. The Social Security Administration does not delay in imputing the death of a recipient.

If you're talking about the LAST Social Security check payment, the answer is NO. It's not yours to "claim".
The government takes back the whole amount for the month he died.
In other words, NO ONE gets to keep the last Social Security check that was paid. The government will TAKE it back. If he doesn't have it in the bank, and you took it out, then YOU would owe the government all of it.

If you're talking about the money your family member had in the bank, like a savings account, then you would need to contact the bank (with a copy of his death certificate) if you were his POA.
Or contact whoever is the conservator or someone taking care of his personal finances to see if he had a will or trust.

So, if you have to be alive the whole day then you can't die till12 am or later which takes you into the next month.

Just to clarify
From ssa.gov;
Being eligible throughout the month applies to the month of death of a Social Security beneficiary. To be eligible for the payment, the person must have lived "all month long" to receive the payment that comes the following month. That includes throughout the entire last day of the month.

Your survivor may be eligible for a payment for the last month and should contact us at 1-800-772-1213. For information about applying for survivors benefits, visit our website at www.socialsecurity.gov/planners/survivors/howtoapply.html.

They will withdraw it. My Dad passed away on January 31, they took the January $$$ out of his account!!!

My mom died on November 28th. By the end of the first week of December the money was gone from her account.

I believe they pay a month in advance ,even so they probably won’t take the whole months check back because he was still alive up until the 18 if there is a overpayment they will normally let you make payment arrangements to pay back How do I know? My son was on ssi until he died I used his ssi checks to help pay for his funeral I made arrangements and paid them back monthly

Dosent social security pay a month in advance ?

No. You can’t keep it. Leave it in the bank account, SS will take it back.

Nope. SS is pretty tight on the accounting.

No. Social Security does not pay for the month of death, even if the person died on the last day.

I don't think so. they probably going to take it back. or send a letter asking for payment.