I missed the April 15th deadline to make contributions to my solo 401K (I had chosen "maximize contribution" with turbo tax). What are my options now ?

[Carl]

Start making 2018 contributions? What other options are you expecting? I'm quite honestly at a loss. Maybe you reported on your 2017 return that you did "in fact" make the contribution when you did not? If so, then you need to file an amended 2017 return now, to remove that contribution from your tax return that you did not make.

[psman]

I reported on the 2017 return at the time of filing, that I did make contribution (as was my intention but I missed the April 15th deadline to make the contribution. TT tells one how much one can contribute at the time of filing but one has until tax deadline date to make the deposit). I am trying to find out if there is a way to contribute to the solo 401K for 2017 after the tax deadline. Filing an amendment to remove that contribution would be the other option, but I would like to be sure that the first option is not possible anymore.

[dmertz · Accepted solution]

If you did not request a filing extension by the regular filing deadline, your only option is to amend your 2017 tax return to remove the deduction for the self-employed retirement contribution that you failed to make.