Can I assist by typing out my response? Saves waiting for a phone call.
A Federal tax deposit that is more than 15 days late is charged a 10% penalty of the entire payment under IRC §6656(b)(1)(A)(iii).
There is also interest charged, which is still pretty low. Specific dates are required to look that up, and the time late is not much. I would estimate 3.5% for 45 days, or approximately .4375%. IRS will bill, and you can use this to test their math accuracy.
If you still need to call, I'll look back in.
You might be able to request a penalty abatement under IRS' FTA, or first time abatement, program. They give almost every taxpayer a 'mulligan', if you will, for missing a due date due to reasonable cause.
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