Absolutely, the e-file fee you paid for 2016 is deductible in your 2017 income tax return.
Assuming you are using the cash method of accounting, your expenses will be deductible in the year the actual payment is made, which in your case was 2017.
For more information on accounting periods and methods, please visit this IRS publication: <a rel="nofollow" target="_blank" href="
https://www.irs.gov/publications/p538">https://www.irs.gov/publications/p538</a>
