I don’t know how the penalty part works on an amended return. Someone else will have to post about that.
No you don’t need to attach the original 1040 when you amend. Did you mail the original return and get the first refund? Mailed returns take a long time to process. Was it for the amount on line 35a or did the IRS adjust it for the penalty. It’s common for the IRS to reduce or increase the penalty. So don’t amend until you get the first refund and see what the IRS did with the penalty.
You can try going through the penalty section to reduce it. If Turbo Tax calculates a penalty on 1040 line 38…..You might be able to eliminate it or at least reduce it. You can go to Federal Taxes tab or Personal tab, under Other Tax Situations and select Start by the Underpayment Penalties. You will answer a series of questions that may reduce or eliminate the penalty. Or you can elect to have the IRS figure the penalty for you. It's form 2210.
It's under
Federal or Personal (for Home & Business Desktop)
Other Tax Situations
Additional Tax Payments
Underpayment Penalties - Click the Start or update button
