CA tax payment in 2018 for 2010 return

[Daniel-G-]

In 2018, I made a payment to CA State as an adjustment to my 2010 tax refund. My CA refund was included as taxable in my 2011 federal return. Can I enter the CA payment amount in my 2018 tax return to receive back tax I paid on the 2010 amount from the federal? Or is my only option to amend my 2011 with the federal to reduce the amount of CA State tax refund? 

[Eric_S]

Yes, you can enter the CA tax paid as an itemized deduction for 2018.  

It is too late to amend a 2011 return.  Generally you have three years from the date you filed a return to amend.