Good question. The contribution limit if you’re married is effectively double what it would be for individuals (provided you and your spouse both participate in individual 401k plans):
If you’re 49 or younger: If you each contribute $17,000 tax-deferred to your respective 401k plans then as a couple you would have reduced your taxable income by $34,000. The big assumption here is that you both have your own 401k plans through your respective employers.
If you’re 50 or older: If you’re eligible to contribute $22,500 (50 or over) then you could contribute $45,000 if you both had your own accounts.
If only one of you participates in a 401k plan then you will have to pick some alternate investment accounts such as a Spousal IRA.
The same logic follows for an IRA. If you’re married just double the amount that individuals are eligible for. Remember that both of these retirement vehicles are individual retirement accounts so your filing status doesn’t impact your contributions (but your combined income may impact your eligibility for traditional and Roth IRA plans).
*Contribution limits are for 2012.
Source: IRS 401(k) Resource Guide
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