I'm an US citizen for over ten years now and my parents just became citizens, what do they need to do to get social security benefit?
P.S.: "they have their tax ids for 9y"
Any information is appreciated!
They need to pay FICA taxes enough to accumulate 40 credits (i.e.: 10 years with ~16K taxable wages/year). They do not have to be citizens for that, so taxes they already paid also count.
Otherwise, if they're over 65 they'll be eligible for medicare 5 years after getting their green card, but may need to pay the premium for medicare part A.