Optimizing Taxes: Backdoor Roth IRA Contributions

This unique strategy becomes available if your 401(k) plan allows you to roll over an IRA account into the 401(k) plan. Normally, single people making over $120,000 a year and married people filing taxes jointly making over $189,000 a year are limited in their ability to contribute to a Roth IRA (the income numbers are based on your Modified Adjusted Gross Income). By using the backdoor Roth IRA strategy, a highly compensated individual can contribute to a non-deductible IRA and convert it to a Roth IRA. The problem is that any Roth conversions must be done pro-rata across all IRA accounts. This means that, if you have a deductible IRA in addition to a non-deductible IRA being funded, any conversion of IRA money would be taken from both pre- and post-tax IRA accounts pro-rata. This creates a tax on the distributions from the deductible IRA where otherwise there would be none. 

To avoid this additional taxation, you could potentially transfer the deductible IRA money into your 401(k) and then convert the new non-deductible IRA contributions to a Roth IRA without creating a taxable distribution.