JANUARY
15th	Estimated tax payment for the fourth quarter for both Federal and State.
15th	Payment in full of estimated tax by farmers and fisherman unless income tax returns are filed by March 1st.
31st	If you did not pay owed estimated tax on January 15, file your personal income tax return and pay tax due to avoid penalties for underpaying estimated taxes (unless you are a farmer or fisherman).
MARCH
1st	Last day for farmers and fisherman who owed, but did not pay estimated tax on January 15, to file calendar year income returns and pay tax to avoid late payment penalty.
APRIL
15th	File your personal tax return (use Federal Form 1040 and Form 2 for Montana) or file for an automatic four-month extension. To file used Federal Form 4868 and pay amount due with extension.
15th	Pay the first estimated tax payment for individuals (use Federal Form 1040ES and Form ESV for Montana).
JUNE
15th	File your individual tax return if you were living outside of the United States (and not subject to withholding) and did not file an extension
15th	Pay the second estimated tax payment for individuals (use Federal Form 1040ES and Form ESV for Montana).
AUGUST
15th	File your individual income tax returns (use Federal Form 1040 and Form 2 for Montana) if you filed for an extension or file Federal Form 2688 to request an additional two months extension of time to file.
SEPTEMBER
15th	Pay the third estimated tax payment for individuals (use Federal Form 1040ES or Form ESV for Montana).
OCTOBER
15th	Last day to file Individual tax return (use Federal Form 1040 and Form 2 for Montana) by individuals who were granted an additional two-month extension of time to file.
DECEMBER
31st	Last day for charitable contributions to be eligible on your tax return, both Federal and Montana.