I think the first $15,000 contributed to a mini or solo 401k makes a lot of sense. You can contribute $1 for every $1 of SE income. Tax-free compounding will make up for the SE taxes, as long as you're earning decent investment returns over at least a decade or two.
As for "profit sharing," which allows you to contribute up to $42k to your solo 401k, I don't think it makes sense. You have to pay SE tax on $1 for every $0.25 contribution. That's pretty hard to justify even with the beneficial treatment of investment returns.
If your spouse can be considered an employee of your business, you can each contribute $15k to the plan, with only $30k of total SE income. This is allowed even if one or both of you has another employer with another 401k plan, as long as each of you contribute no more than the $42k individual limit.
Keep in mind that, in theory, the SE taxes are a transfer payment that benefit you when you retire. So it might not be money down the drain. If you haven't already maxed out your Social Security lifetime income, the SE taxes you pay on earned income will increase your SS benefit. That is, assuming SS isn't bankrupt by the time you retire.
Martin
As for "profit sharing," which allows you to contribute up to $42k to your solo 401k, I don't think it makes sense. You have to pay SE tax on $1 for every $0.25 contribution. That's pretty hard to justify even with the beneficial treatment of investment returns.
If your spouse can be considered an employee of your business, you can each contribute $15k to the plan, with only $30k of total SE income. This is allowed even if one or both of you has another employer with another 401k plan, as long as each of you contribute no more than the $42k individual limit.
Keep in mind that, in theory, the SE taxes are a transfer payment that benefit you when you retire. So it might not be money down the drain. If you haven't already maxed out your Social Security lifetime income, the SE taxes you pay on earned income will increase your SS benefit. That is, assuming SS isn't bankrupt by the time you retire.
Martin
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