In Oklahoma, how far back can I claim unused Wire Transfer Fee credits? Is it just for the previous year (e.g. 2017 for tax year 2018?) or can I go further back?

[AnthonyC]

You can go back five years.

From OK form 511-DR "A Wire Transfer Fee Credit that was established in a prior year but not used due to the limitations provided may be carried over. The unused credit may be carried over for a period not to exceed five years. 68 OS Sec. 2357.401 and Rule 710:50- 15-111d"

Note:  This credit was not available to be established in 2017, so you actually wouldn't be able to include that year.  Also, the credit would have needed to be established on the tax return in order to carry forward the amount.  Thus, if you didn't claim these credits in a prior year, you may need to amend your OK tax returns to include the credit and carryforward.