I am a Delaware resident but I work and rent in ny. What will be more beneficial: changing my state of residency to ny or leaving it as it is now (DE)?

If you live in NY.. then you don't legally have a choice... you have to change it to NY or deal with tax evasion charges when they catch you.

Ny can and would pursue this once they figure it out.

While being somewhat dramatic with his wording, Smoothy effectively has it right: you probably alreay ARE considered to be a New York resident.

But tax evasion is not my intent... I didn't move cause I have a son in HS and don't want to move him in his Junior year.
I rent a room in NY but own house in DE. Does the fact that I am a homeowner in DE makes me a resident?

Doesn't matter.. where you own houses and how many... you live in NY... that makes you a NY resident for legal and tax reasons.

That's like saying I own a House in Florida... so I don't have to pay income tax... it doesn't work that way... if you stay in a place for 50.0000001% of the time.. that is your residence. And you would not win an argument with the NY tax authorities.

You could only claim Delaware if you drove a back and forth to Delaware every day.

Actually, it is NOT quite as cut-and-dry as Smoothie states; intent DOES make a difference.

HOW LONG have you been renting an apartment in NY state?