Adding a dependent on your tax return increases the exemption amount you can claim, which in turn reduces your taxable income and your tax liability. Dependents can also be used to gain tax benefits like the child and dependent care credit and head of household filing status.
http://www.investopedia.com/articles/tax/09/claim-a-dependent.asp
In addition to meeting the qualifying child or qualifying relative test, your child must also meet all of the other tests for claiming a dependent: 1  Dependent taxpayer test. 2  Citizen or resident test, and. 3  Joint return test.
https://www.irs.gov/help-resources/tools-faqs/faqs-for-individuals/frequently-asked-tax-questions-answers/filing-requirements-status-dependents-exemptions/dependents-exemptions/dependents-exemptions-2
When you’re claiming a dependent who is a child, there are further requirements: 1  The child has to have lived with you for at least half of the year. 2  The child has to be related to you as a son, daughter, stepchild, foster child, brother, sister, stepbrother, stepsister, or a descendant of any of those.
https://www.1040.com/tax-guide/taxes-for-families/who-can-you-claim/
Rules that Apply to Your Dependents. 1  You can't claim a dependent who is married and files a joint return — with one exception. 2  Your dependent must be a U.S. citizen, a national or resident alien of the United States, or a resident of Canada or Mexico. 3  A dependent can be claimed by one and only one taxpayer in any given year.
https://www.thebalance.com/claiming-dependents-3193028
A dependent is a person other than the taxpayer or spouse who entitles the taxpayer to claim a dependency exemption. Each dependency exemption decreases income subject to tax by the exemption amount. The exemption amount for 2014 is $3,950. A dependent may be either a Qualifying Child or a Qualifying Relative.. A. To claim a dependency exemption for a qualifying child, all of the qualifying child dependency tests must be met: 1  Dependent Taxpayer Test. 2  Joint Return Test. 3  Citizen or Resident Test.  Relationship 1  Test. Age Test.  Residency 1  Test. Support  Test.
https://apps.irs.gov/app/understandingTaxes/teacher/hows_mod04.jsp
To claim your child as your dependent, your child must meet either the qualifying child test or the qualifying relative test: 1  To meet the qualifying child test, your child must be younger than you and either younger than 19 years old or be a student younger than 24 years old as of the end of the calendar year. There's no age limit if your child is permanently and totally disabled or meets the qualifying relative test.
https://www.irs.gov/help-resources/tools-faqs/faqs-for-individuals/frequently-asked-tax-questions-answers/filing-requirements-status-dependents-exemptions/dependents-exemptions/dependents-exemptions-2
Updated January 27, 2017. Claiming one or more dependents on your tax return can save you a fair bit of money. The Internal Revenue Code is set up to allow taxpayers to deduct personal exemptions for themselves, as well as for each dependent they claim. These deductions subtract from the income they must pay taxes on.
https://www.thebalance.com/claiming-dependents-3193028
Because it could save you thousands of dollars on your taxes. For every qualified dependent you claim, you reduce your 2016 taxable income by $4,050. This can add up to substantial savings on your tax bill. Dependent rules also apply to other benefits, such as tax credits. Many of these credits are available only if you have qualified dependents.
https://turbotax.intuit.com/tax-tools/tax-tips/Family/Rules-for-Claiming-a-Dependent-on-Your-Tax-Return/INF12139.html
Before claiming someone as a dependent on your tax return, you have to make sure that the person meets all the Internal Revenue Service (IRS) requirements for a dependent. TUTORIAL: Personal Income Tax Guide. A dependent is usually defined as someone you support or take care of.
http://www.investopedia.com/articles/tax/09/claim-a-dependent.asp
Qualifying children and qualifying relatives have their own additional requirements, but all dependents must meet these requirements: 1  Dependents can have their own tax returns, and even be married, but they must not have filed a joint tax return for the year unless it’s just to claim a refund. They must be a U.S. citizen, U.S. national, or a resident alien. They must have a taxpayer identification number.
https://www.1040.com/tax-guide/taxes-for-families/who-can-you-claim/
minimum age to claim dependents for tax purposes
To claim your child as a your dependent, child meet the qualifying child test in which child must be younger than you and either younger than 19 years old or be a student younger than 24 years old. To claim dependents for tax purposes, your child must be younger than you and either younger than 19 years old or be a student younger than 24 years old as of the end of the calendar year.