For the federal, you would need to be using Turbotax for 2017, which at this point can only be installed on your own computer as a download or from a CD (not online). Assuming you have your final tax return and tax data file from 2017, you would determine the amount of the credit by adjusting box 1 of the W-2, and then noting the difference in your income tax on form 1040 line 55, before and after the adjustment. That is the amount of credit you can take on line 74 for 2018.
You don't want to use Turbotax 2018 to calculate the amount of the credit because the tax rates changed.
There are also instructions to calculate the credit in publication 525, although they may refer you to manual calculations using the 2017 forms and instructions. <a rel="nofollow" target="_blank" href="
https://www.irs.gov/forms-pubs/about-publication-525">https://www.irs.gov/forms-pubs/about-publicati...>
Arizona does have a Claim of Right form and instructions if you search their web site, the limit is the same as the IRS, $3000 or more.
<a rel="nofollow" target="_blank" href="
https://azdor.gov/forms/individual/individual-form">https://azdor.gov/forms/individual/individual-fo...>
I don't know where it will be in Turbotax, but the state modules usually have one or more screens of state-specific additions to income and state-specific deductions and credits. If you can't find it, you can try searching, or call Turbotax customer support and ask for an Arizona specialist.
