Inheritances are tax free, regardless of amount. However, if the account starts to earn interest, your spouse must pay tax on the interest from the date of the inheritance.
Advance payment of current tax liability based either on wage withholdings or installment payments of your estimated tax liability. To avoid penalties, you generally must pay to the IRS either 90% of your final tax liability, or either 100% or 110% of the prior year’s tax liability, depending on your adjusted gross income.