I'm not sure what you mean by "owe a balance."
If you mean that you made a mistake in 2016, and if you amended it you would owe additional tax, then you can amend any time (to pay more tax). You will need to amend by hand, or find a tax professional, because Turbotax no longer sells or supports the 2016 version. You will also owe interest and a late payment penalty (which you might be able to negotiate, since you are voluntarily fixing your mistake). The statute of limitations for most returns is 3 years, or 6 years if the amount of under-stated tax was more than 25% of your total tax. So the statute of limitations either ran out April 15, 2020, or will run out April 15, 2023. You might decide to let sleeping dogs lie and not pay the extra tax.
If you mean, you owe money on your IRS account and you think you can reduce the amount you owe by filing an amended return, that probably won't work. Refunds aren't paid if you amend more than 3 years late, or more than 2 years after you filed, if you filed late to begin with. And, while refunds definitely won't be paid in cash, I think they also won't be credited to a past due amount, although I am less sure about that.
Based on the three-year rule, you have until April 15, 2020, to file an amended 2016 return and claim your refund.
I'm not sure what you mean by "owe a balance."
If you mean that you made a mistake in 2016, and if you amended it you would owe additional tax, then you can amend any time (to pay more tax). You will need to amend by hand, or find a tax professional, because Turbotax no longer sells or supports the 2016 version. You will also owe interest and a late payment penalty (which you might be able to negotiate, since you are voluntarily fixing your mistake). The statute of limitations for most returns is 3 years, or 6 years if the amount of under-stated tax was more than 25% of your total tax. So the statute of limitations either ran out April 15, 2020, or will run out April 15, 2023. You might decide to let sleeping dogs lie and not pay the extra tax.
If you mean, you owe money on your IRS account and you think you can reduce the amount you owe by filing an amended return, that probably won't work. Refunds aren't paid if you amend more than 3 years late, or more than 2 years after you filed, if you filed late to begin with. And, while refunds definitely won't be paid in cash, I think they also won't be credited to a past due amount, although I am less sure about that.