A contribution to a 401k at work reduces the income in box 1 of the W2 and thus the earned income. I thought that a contribution to a solo 401k from a 1099-misc as an independent contractor also would decrease the earned income. However, when I enter the contributions on the turbo tax software it does not change the earned income or the earned income tax credit. Is there then a crucial difference in how a regular 401k is treated vs. a solo 401k? Or am I making a mistake in how I enter the information?