My 19-year-old started working a few months ago does he claim himself with his w-2s or does he still get claimed under mine since he still lives at home.

[DoninGA]

If he is not a full time student and has gross income of $4,400 or more in 2022 then you cannot claim him as your dependent under the Qualifying Relative rules.

He files his own tax return for tax year 2022 and does NOT indicate on his return that he is a dependent.

To be a Qualifying Relative -

1. The person cannot be your qualifying child or the qualifying child of any other taxpayer. A child is not the qualifying child of any other taxpayer if the child's parent (or any other person for whom the child is defined as a qualifying child) is not required to file an income tax return or files an income tax return only to get a refund on income tax withheld.
2. The person either (a) must be related to you or (b) must live with you all year as a member of your household.
3. The person's gross income for the year must be less than $4,400 (social security does not count) in 2022
4. You must provide more than half of the person's total support for the year.
5. The person must be a U.S. citizen or a U.S., Canada, or Mexico resident for some part of the year.
6. The person must not file a joint return with their spouse.

[xmasbaby0]

If your 19 year old is not a full-time student and he earned more than $4400 in 2022 then you cannot claim him as a dependent.  He can file his own tax return and say that he cannot be claimed.

If, however, he has been a full-time student in 2022, that changes it.  Was he a student?

IRS interview to help determine who can be claimed:

https://www.irs.gov/help/ita/who-can-i-claim-as-a-dependent

https://ttlc.intuit.com/questions/3113432-who-can-i-claim-as-my-dependent  

WHO CAN I CLAIM AS A DEPENDENT?

You can claim a child, relative, friend, or fiancé (etc.) as a dependent on your 2022 taxes as long as they meet the following requirements:

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.

Qualifying relative

• They don't have to be related to you (despite the name).
• 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 lived with you the entire year (exceptions apply).
• They made less than $4,400 in 20222.
• You provided more than half of their financial support.

When you add someone as a dependent, we'll ask a series of questions to make sure you can claim them. There may be other tax benefits you can get when you claim a dependent.

[NCperson]

@mathews1016 - best to use the IRS tool to determine whether your child is a dependent or not.  However, as other stated, if not in school and earns more than $4400, he can not be a dependent.  

https://www.irs.gov/help/ita/whom-may-i-claim-as-a-dependent

whether a dependent or not, his income goes on his tax return and not yours.  If he earned at least $12,950 as a W-2 employee he is required to file.  Otherwise, there is no filing requirement, but it is the only way to get back any withholdings.  State rules may be different. 

[Mike9241]

there are different rules if he's your qualifying child.   the issue of whether he's a qualifying child or a qualifying relative probably depends on his student status since he's over 19

you can claim him as a qualifying child if all these tests are met
• he has the same principal abode as you for more than ½ the tax year. Temporary absences like for school are ignored
• if he is not a full-time student, he's under 19 at the end of the tax year. If a full-time student, he's under 24 at the end of the tax year. 
• he hasn't provided over ½ his own support
• he didn't file a joint return unless there was no tax liability but merely filing jointly to facilitate a refund of taxes withheld or estimates paid

a full-time student is one who is enrolled full-time in school (but not online or correspondence schools) during any part of 5 calendar months during the calendar year  

he would still file his own return to report his income. if he is a dependent you can claim, he must so indicate on his tax return even if you do not in fact claim him on your return.