Odd 401k question

[acanthurus]

So I switched jobs this year.

At the old employer, I had really bad 401k plan (terrible fees and vesting schedule) and knew I was going to be leaving this year before any match could vest. I hit the federal contribution limit of 17.5K in April. My thinking was I didn't know when I was going to find that next job, or where, and some places make you wait 3-6 months to be eligible for the 401k, so I thought I'd make sure I got all the taxed advantaged savings I could as soon as possible.

I managed to find a better job much faster than expected, and changed jobs in July. Old 401k is now in a rollover IRA at Vanguard with a nice .05% ER total market fund.  New employer has an AWESOME 401k plan, with a 5% match and a 4% kicker and it vests quickly. New employer does NOT allow post-tax contributions.

Is there any way I can contribute pre-tax money (as far as my new employer is concerned) up to the match, but not claim the contributions as pretax on my income taxes? I basically want to be contributing post-tax dollars (as far as the govt is concerned), which I know will get taxed again upon distribution, to get the 5% match. I would NOT be contributing anything beyond what's required to get the match.

[minimalist]

Yes. You will be taxed for the year you earned it and when you withdraw it (double taxation). You may want to change your payroll exemptions to avoid IRS interest tax penalties. You may also correct the overage before April 15 of the following year if you change your mind.

[acanthurus]

So as long as I'm fine with double taxation on the excess contribution to get 100% return from the match, this is a no brainer, right? After bonus I'll be in the 28% bracket this year.

There's 4.5 months left in the year, so the match I could get would amount to $1500 at my current salary. I hate passing up free money, I just want to make sure I'm not making a tax headache for myself down the road.