The qualification for earned income tax credit (EITC) is based on your adjusted gross income (AGI) and earned income. To be eligible for the credit with one child, your AGI on line 8b must be less than $41,094 (or $46,884 if married filing jointly). Those "maximum amounts" also apply to your earned income, which is the taxable income and wages you get from working or certain disability payments.
A good tool for understanding eligibility for EITC is the IRS guide at this link.
Are you sure you're looking at line 18a and not line 13a?
The $500 is the "Other Dependent Credit", for those who's child is too old (or otherwise doesn't qualify) for the Child Tax Credit. It's new, stating in 2018. It is unrelated to the EITC. The credit for Other dependents shows on line 13a of form 1040. Any EITC will be on line 18a. Your line 18a is probably blank.
There are several child-related credits you *may* get if you have a dependent child and if you have income earned from working.
You might be getting the Child Tax Credit--that is not all a refund--it lowers the tax you owe, up to $2000 per child, but if you do not owe tax then you may not get the full amount of CTC. In some cases, you could qualify for the "Additional Child Tax Credit" which is a refundable credit, and would increase your refund. If you qualify for this credit, TurboTax calculates and automatically adds it to your refund.
You might be able to claim the child and dependent care credit if you paid someone to take care of your child so you could work. This is not a refundable credit, so it will not be in your refund. It can lower the tax you owe.
You might qualify for Earned Income Credit, which is a refundable credit if you worked and earned income. The EIC is based on the amount you earned. If you do qualify for EIC, TurboTax automatically calculates the amount and adds it to your refund.
Look at your 2019 Form 1040 to see the child-related credits you received
PREVIEW 1040
https://ttlc.intuit.com/questions/1901539-how-do-i-preview-my-turbotax-online-return-before-filing
Child Tax Credit line 13a
Credit for Other Dependents line 13a
Earned Income Credit line 18a
Additional Child Tax Credit line 18b
Child and Dependent Care Credit line 18d
https://ttlc.intuit.com/questions/1900923-what-is-the-child-tax-credit
https://ttlc.intuit.com/questions/1900643-what-is-the-child-and-dependent-care-credit
https://www.irs.gov/credits-deductions/individuals/earned-income-tax-credit/use-the-eitc-assistant
The qualification for earned income tax credit (EITC) is based on your adjusted gross income (AGI) and earned income. To be eligible for the credit with one child, your AGI on line 8b must be less than $41,094 (or $46,884 if married filing jointly). Those "maximum amounts" also apply to your earned income, which is the taxable income and wages you get from working or certain disability payments.
A good tool for understanding eligibility for EITC is the IRS guide at this link.
Are you sure you're looking at line 18a and not line 13a?
The $500 is the "Other Dependent Credit", for those who's child is too old (or otherwise doesn't qualify) for the Child Tax Credit. It's new, stating in 2018. It is unrelated to the EITC. The credit for Other dependents shows on line 13a of form 1040. Any EITC will be on line 18a. Your line 18a is probably blank.