Can I claim my 17 year old son even though we live with my mom and dad and they paid more of his financial expenses than I did

[MayaD]

Yes, you can claim your son even if your parents paid more of his financial expenses.  Assuming that you can't be claimed as a dependent on your parent's return.

Qualifying child

• They're related to you.
• They aren't claimed as a dependent by someone else.
• They're a U.S. citizen, resident alien, national, or a Canadian or Mexican resident.
• They aren’t filing a joint return with their spouse.
• They're under the age of 19 (or 24 for full-time students).
  • No age limit for permanently and totally disabled children.
• They lived with you for more than half the year (exceptions apply).
• They didn't provide more than half of their own support for the year.

Who can I claim as my dependent?

[Edited 02/06/2024, 10:40 AM ,PST]

[Opus 17]

If the child lives with parent and grandparent more than half the year, then either the parent or the grandparent can claim the child as a dependent, but the parent always gets first choice.

The support test for a dependent under age 19 is "the child did not pay more than half his own support."  It doesn't matter who paid the support as long as the child did not pay his own support.