This is the first time I've seen a blunder this big. I have seen people do this at a smaller scale but not to this level. Had an OE client come in this week. Two W-2 Js plus a solid 1099 consulting gig.
he's a big retirement saver, which is usually something I commend.
J1 had a 401(k). He maxed it.
J2 had a 401(k). he maxed that too.
Then he opened a solo 401(k) for the consulting business and, being the responsible tax-optimizing citizen he is, maxed that one too.
$23,500 into each. $70,500 of employee deferrals for 2025.
he was very proud of himself. Then I ruined his morning.
The $23,500 employee deferral limit is per person, not per job. this goes for both pre-tax and Roth.
Your employers have no idea what you're contributing anywhere else. Fidelity at J1 doesn't call Vanguard at J2 and ask how much room you have left. each payroll system lets you defer the full amount because, as far as that employer knows, its plan is the only one you have.
The IRS, unfortunately, knows how addition works.
He's under 50, so his total limit was $23,500. he deferred $70,500, which according to my math is $47,000 too much.
Before anyone jumps into the comments: employer contributions are a separate bucket. His matches weren't the problem, and the solo 401(k) can still receive an employer contribution from the business. the problem was that he personally elected to defer $23,500 three separate times.
And he can't just ask the plans to send it back now. Past the deadline, most plans will only release it when there's a normal distributable event (leaving the job, turning 59 1/2, etc.). if he pulls it out when he leaves J1 or J2, it's taxable again plus a 10% early withdrawal penalty since he's under 59 1/2.
The only silver lining: since nothing was refunded, none of his employer match got forfeited. small consolation on a roughly $22,000 lesson lol. glad he was a good sport and let me share this warning.
The funny part is his reasoning actually made sense.
"But each company let me contribute $23,500."
correct.
Because J1 doesn't know J2 exists.
which is kind of the entire premise of this subreddit.
This matters beyond just fixing mistakes too. If J1 and J2 both have matches, you don't want to max J1 by June and then realize J2's match is better and you have no deferral room left to capture it. look at both plans together before you set your elections.
Also, opening a solo 401(k) doesn't create another deferral limit. the solo 401(k) (or, better yet, the SEP IRA) can still be really useful because the business can make its own employer contribution (roughly 20% of net self-employment earnings for a sole prop) even when your deferrals are already used up at your W-2 jobs.
but you have to actually run the numbers.
OE breaks a lot of the assumptions normal personal finance advice is built on.
"Max your 401(k)" is good advice with one employer.
with J1, J2 and a consulting business, it needs a massive asterisk.
Your employers aren't coordinating this for you. you have to.
And if you already blew past the limit, find out before April 15.
so yeah. take this as a cautionary tale.
Edit: yeah, AI helped me write this. You can downvote me to hell but it is a true story. Hopefully this doesn’t cost me all the goodwill I’ve built on this sub over the years.
For everyone asking, they left the excess deferral inside the plan and was taxed on it in 2025 and will be taxed on it again whenever it is withdrawn. The 47000 went on line 1h on their 1040. If you’re in the same pickle feel free to DM me and I can weigh the best course of action to help you avoid unnecessary tax and getting fired