Ira contribution which I could NOT deduct

[Llctaxlearner]

For 2021 , due to total AGI I could not deduct my 6k ira contribution 

since I already made contribution and now since it’s post taxes , would I have to pay taxes when in future I take distribution ?

[ErnieS0]

You do not pay tax on any contributions that you could not deduct. You will pay tax on any earning.

For example, if you contributed $6,000 in after tax money to your IRA and it grows to $10,000 when you decided to withdraw it, then only $4,000 will be taxable ($10,000-$6,000).

TurboTax will keep track of this after tax basis.

[Llctaxlearner]

Since it was not deductible eligible I didn’t report , how do I correct it ?

plus several years dow the road when I do withdraw , how would Irs know only 4000 assuming gain is only taxable ?

[SundayInSalem]

Report your nondeductible IRA contribution on Form 8606 so you and IRS have a record that you made a nondeductible contribution.

TurboTax will create Form 8606 if you enter a nondeductible contribution. You can amend your return.

How do I amend my 2021 return?

When you do withdraw from an IRA several years down the road, Form 8606 will be your proof that you made a nondeductible contribution.