Unfortunately when it comes to the Medicare premiums the IRS will combine both MFS returns to determine the income test for the medicare Premiums. Sorry
A trick to consider - if you approach year end and know you are underpaid with estimated taxes - you can cure the problem by having your employer make extra wit...
While the penalty is small you might want to look at your withholdings at each Quarterly testing date.You can compute the penalty by claiming the actual amount ...
