Spreadsheet to Play with 401k Contributions

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raamakoti
Posts: 27
Joined: Mon Jul 31, 2017 10:20 am

Spreadsheet to Play with 401k Contributions

Post by raamakoti » Fri Aug 11, 2017 11:02 am

Thanks for all the help you guys provide.
I was wondering if there is a spreadsheet or webtool that lets you play with 401k contribution to see the tax savings and total take home pay.
This is for running different scenarios to see what works best.
I found mortgage payoff sheets and its really helpful to see payment schedule and how little extra payment make big impact. I wanted to explore similar things with me and my wife's 401k.
I would really appreciate your guidance.

DSInvestor
Posts: 10557
Joined: Sat Oct 04, 2008 11:42 am

Re: Spreadsheet to Play with 401k Contributions

Post by DSInvestor » Fri Aug 11, 2017 11:05 am

Use a tax calculator like HR Block's tax calculator. https://www.hrblock.com/get-answers/tax ... e/aboutYou
First calculate your tax liability without Traditional 401k contributions, then reduce the income by the amount of your Traditional 401k contributions. The difference in fed tax will give you an indication of the change in your take home pay. If you see a $6000 reduction in fed tax, that's roughly $500/month more in take home pay. Note that your state income tax liability may change as well, depending on your state(s). Unfortunately, HR BLock's tax calculator does not handle state income taxes.

Roth 401k contributions do not offer any tax savings.

Be aware that coverage by an employer plan (W-2 retirement plan box is checked), will have implications for Traditional IRA tax deduction. See IRA deduction limits page from IRS: https://www.irs.gov/retirement-plans/ir ... ion-limits

dignan
Posts: 56
Joined: Mon Nov 23, 2015 1:01 pm
Location: chicago

Re: Spreadsheet to Play with 401k Contributions

Post by dignan » Fri Aug 11, 2017 11:25 am

I really like these wage calculators that incorporate deductions. They come really close to what HR calculates at my work. I am able to input HSA and FSA deductions as well as incorporate non-deductible items like dental, etc.
http://www.paycheckcity.com/calculator/401k/
https://www.adp.com/tools-and-resources ... anner.aspx

FloRidaRocky
Posts: 39
Joined: Wed Oct 12, 2016 6:11 pm

Re: Spreadsheet to Play with 401k Contributions

Post by FloRidaRocky » Fri Aug 11, 2017 11:47 am

Can't you just look at the state and federal income tax brackets?
Use the calculator at this link:
http://www.moneychimp.com/features/tax_brackets.htm
For example, you are single, make $100k/year, no 401k contribution, your tax is $20,982.
If you max 401k ($18k), your taxable income is now $82k/year, tax is $16,239, so you save $4,743 in taxes by maxing the 401k.
If you have state income taxes, you'd have to consider that savings too.

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FiveK
Posts: 2890
Joined: Sun Mar 16, 2014 2:43 pm

Re: Spreadsheet to Play with 401k Contributions

Post by FiveK » Sat Aug 12, 2017 12:01 am

raamakoti wrote:Thanks for all the help you guys provide.
I was wondering if there is a spreadsheet or webtool that lets you play with 401k contribution to see the tax savings and total take home pay.
This is for running different scenarios to see what works best.
The spreadsheet tool referenced in Tools and calculators - Personal_finance_toolbox will do exactly that.

Especially if you are looking at the effect of 401k contributions on the saver's credit, etc., that tool is better than TaxCaster and other shortcut tools that omit not-all-that-unusual things such as the saver's credit, etc. It also provides charts instead of single point answers (if you are at least somewhat conversant with Excel).

Of course, full commercial software (TurboTax, etc.) remains best for checking to ensure complete accuracy, whatever you use for estimates.

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