The minimum penalty for accessory after the fact is 16 months in prison and possibly a fine $5,000.00 if the accessory after the fact is a felony that you're convicted of.
It also depends on your prior criminal history as well and you could get 2 years to 3 years in prison as well as that fine.
If it's your first conviction and you've never been to jail or prison before then you might get off with 16 months in prison if you're lucky.
If the accessory after the fact is charged as a misdemeanor which it can be in some places depending on the crime you might only get a year in county jail as well as the $5,000.00 fine.