Is my 25 year old graduate student still a dependent if she has no income.

[hbl3973]

The answer is most likely YES.  Referring to the Form 1040 instructions

   https://www.irs.gov/pub/irs-pdf/i1040gi.pdf

on page 17 it says that the student must have been 24 or less at the end of 2015 to be a dependent "qualifying child".  However on page 18, your 25 year old almost surely fits the dependent "qualifying relative" criteria.  Be sure to confirm for yourself that this is indeed the case and skim over the exceptional special rules that follow on page 19 and 20.

[macuser_22]

Slight correction - it is under age 24 or no older than 23 to be a qualifying child.

[hbl3973]

Good catch.  Thanks.