So you've inherited your spouse's IRA. What you do now could have far-reaching tax implications. The one thing you cannot do is ignore the tax issue. Why? Because if you fail to withdraw at least the required minimum amount from your inherited IRA, you will be charged a penalty equal to 50% of the shortfall. This is one of the toughest penalties in our beloved tax code. So pay attention and read on to learn how to compute 2012 required minimum withdrawals from an IRA you inherited from your spouse.

To learn the specifics for your situation, click on the scenario that applies to you.

• Your Spouse Dies Before the Minimum Withdrawal Start Date
• Your Spouse Dies on or After April 1 of the Year After Turning 70 1/2
• You Want to Disclaim the Inherited Account/Your Spouse's Estate Is the Account Beneficiary

Roth IRAs

Keep in mind, the mandatory withdrawal rules apply to inherited traditional IRAs (including SIMPLE IRAs) and inherited simplified employee pension, or SEP, accounts (since they are considered IRAs for this purpose). Slightly different guidelines apply to Roth IRAs. Specifically, if you have inherited your spouse's Roth and you'd like it to continue to grow tax-free, you should transfer the account to your own name and treat it as your own account. Why? Because with Roth accounts you aren't required to take any minimum withdrawals from your own account as long as you live.

For more: Read Which IRA Is Best?" as well as learn more about choosing an IRA. Also read our IRA guide.