Just a reminder that the due date for 2010 tax returns is April 18, 2011! Normally the deadline is April 15, but when a due date falls on a weekend or holiday, the due date is extended until the next business day. Thus, since April 15 is a legal holiday in Washington, D.C. (Emancipation Day), the due date for 2010 tax returns is extended until Monday, April 18, 2011.
There is no penalty for filing late if you are receiving a refund. However, it is quite a different story if you have a balance due. There are two types of penalties; late filing and late payment and both can be quite severe. Filing an extension gives you until October 17th to file and avoid the late filing penalties. However, there is no extension for paying your tax liability even if you have a valid extension to file.
April 18 is also the deadline for making contributions to either a Roth or Traditional IRA for 2010, even if an extension is filed, and filing your 2011 first quarter estimated tax payment.