“I travel abroad for work. About 30 percent a year working as a consultant abroad. Do i have to pay US taxes on those 100 days while out of the US. I am salaried and reside in the US.”------->I assume that you are a US person,i.e, a US citizen/a green card holder or a US resident for tax purposes, then yes you must pay tax on your income that you earn as a consultant; you are subject to US taxes, fed/state tax, on your world wide and US source income. Once you paid income tax(es) to the foreign taxing authorities on your taxable earned income that you earned abroad, then you can claim your foreign tax(es) on your US returns, fed/state returns. You can choose to take the amount of any qualified foreign income taxes paid or accrued during the year as a foreign tax credit or as an itemized deduction. To choose the deduction, you must itemize deductions on Form 1040, Sch A line 8. To choose the foreign tax credit you generally must complete Form 1116 and attach it to your Form 1040 on line 47. You can contact a tax attorney/a Tax practitioner in your local area for your late fed/state returns. As a consultant, if you are filing as a sole proprietor and/or a self-employed individual, you generally have to make quarterly estimated tax payments if you expect to owe tax of $1,000 or more when you file your return. As long as the amoun ton Sch C of 1040 line 29/31 is $400 or exceeds $400 you need to file your US returns and as long as the amount on Sch SE line 4 is also $400 or exceeds $400, you must pay self employment tax to the IRS.