as to the amount paid and when that's up to the taxpayer but late payments are subject to .5% penalties per month + interest until the balance due is paid in full starting from the original due date which is generally 4/15. if you don't have a valid extension there is also a late filing penalty which is 4.5 % + interest on the balance due for up to 5 months + the late payment penalty.
turbotax does not figure these penalties.
