Three of the most common ways that you can withdraw funds from your IRA without penalty are – reaching age 59 1/2, death, and disability.
When you reach age 59 1/2, you can withdraw any amount of your IRA (or other deferred account) without penalty, for any reason. The only thing you have to remember is that you must pay ordinary income tax on the amount that you withdraw. This means that, once you have reached the date that is 6 months past your 59th birthday, you are free to make withdrawals from your IRA without penalty.
Upon your death at any age, your beneficiaries of your account, or your estate if you have not named a beneficiary, can take distributions from your IRA in any amount for any reason without penalty.
In addition, if you are deemed “totally and permanently disabled” you are also eligible to withdraw IRA assets for any purpose without penalty. Total and permanent disability means that you have been examined by a physician and the disability is such that you can not work, and the condition is expected to last for at least one year or result in your death.
Click the link to pick up a copy of An IRA Owner's Manual or if you'd prefer the Kindle version (and let's face it, ALL the cool kids do!), you can find that at this Kindle version link.Jim Blankenship, CFP®, EA, is an expert in personal retirement, IRAs, and tax issues, with more than 25 years of experience in the industry. Read more from this author

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[...] §72(t)(2)(A)(i) – age 59 1/2. [...]