Individual Tax Deadlines   Individual Returns:  Due April 15th,  can be extended until October 15th There are penalties for filing late and for paying late.  Filing an extension removes the late filing penalty (provided you file by October 15th).  But filing an extension does not give you extra time to pay.  If you owe, the balance is due by April 15th or you will be charged a penalty for paying late.  The failure to file penalty is the worst.  It's 5% of the balance due per month, not to exceed 25%.  The failure to pay penalty is .5% (one half percent) of the balance due per month. Individual Estimated Tax Payments:  Apr 15, Jun 15, Sep 15, Jan 15 There is yet another penalty for underpaying estimated taxes.  Generally, you need to pay 90% of the current year taxes or 100% of the prior year taxes, whichever is less.  (If your AGI was over $150K for the prior year, then it's 90% of the current year or 110% of the prior year, wichever is less.)  If you owe less than $1000 when your return is completed, then no penalty for underpayment of estimated taxes will be due. It is not necessary that you make four equal payments.  You can adjust your estimated tax payments according to your income.