Internet TAXSIM Version 35

Internet TAXSIM test

This is a test version of taxsim35. Please be careful.

Calculate liabilities for one taxpayer (fill every box)

Marginal Rates with respect to: Other Income Wage Income Taxpayer Earnings Spouse Earning Long Term Gains Dividends Other deductions Dividends Mortgage Interest Don't bother

Optional tax plan(s). Usually zeroes.

Basic Data
1. taxsimid Case ID (arbitrary, but non-negative numeric)(x1)
2. year Tax year ending Dec 31(4 digits between 1960 and 2023, but state must be zero if year is before 1977. (We don't have code for state laws before 1977.) State tax laws are effectively inflated by 2.5%/year after 2021.
3a. state SOI state codes. These run from 1 for Alabama to 51 for Wyoming. See list. Use zero for "no state tax calculation".
3b. statefip FIPS state codes. These run from 1 for Alabama to 56 for Wyoming. See list. An alternative to state.
4. mstat Marital Status
  • 1. single or head of household (unmarried)
  • 2. joint (married)
  • 6. separate (married). Note that Married-separate is not usually desirable under US tax law.
  • 8. Dependent taxpayer. (Typically a child with income).
Head of Household status is determined by taxsim35 from dependent information. Unmarried taxpayers with dependents are assigned head-of-household.
5. page Age of primary taxpayer December 31st of the tax year (or zero). Taxpayer and spouse age variables determine eligibility for additional standard deductions, personal exemption, EITC and AMT exclusions.
6. sage Age of spouse (zero if unknown or not a joint return). It is an error to specify a non-zero spouse age for an unmarried taxpayer.
7. depx Number of dependents (for personal exemption calculation). If no age variables are non-zero (here on the web form) or if no age variables are present in the file (for file submission), then depx will be used as the number of EIC eligible children. You can negate this assumption by putting a large number (such as 99) in the age1 field.
8. age1 Age of first dependent. Used for EITC, CTC and CCC. For 1991+ code students between 20 and 23 as 19 to get the EITC calculation correct. Code infants as "1". Leave as zero for no dependents. [For compatibiity with taxsim32, dep13-dep18 are accepted and have priority over age1-age3]. For file uploads, if neither dep19 or age1 are present in an uploaded file than depx is used for the number of child eligible for the EIC, CTC and CDCC.
9. age2 Age of 2nd dependent.
10. age3 Age of 3rd dependent. Ages of any additional dependents are not relevant for the tax calculation, but all dependents should be included in 7. depx. age1...age3 may be in any order, but should be the 3 youngest dependents to minimize tax liability.
11. pwages Wage and salary income of Primary Taxpayer
12. swages Wage and salary income of Spouse (exclude QBI). Note that this must be zero for non-joint returns. Watch out for this if you use current marital status and last year's income, which will happen in survey data.
13. psemp Self-employment income of Primary Taxpayer (exclude QBI).
14. ssemp Self-empoyment income of Spouse
15. dividends Dividend Income (qualified dividends only for 2003 on).
16. intrec Taxable Interest Received. After 2003 unqualified dividends can go here.
17. stcg Short Term Capital Gains or losses. (+/-)
18. ltcg Long Term Capital Gains or losses. (+/-)
19. otherprop Other property income subject to NIIT, including
  • unearned or limited partnership and passive S-Corp profits
  • rent not eligible for QBI deduction
  • non-qualified dividends
  • other taxable income or loss not otherwise included
20. nonprop Other non-property income not subject to Medicare NIIT such as:
  • alimony
  • nonwage fellowships
  • state income tax refunds (itemizers only)
Adjustments and items such as
  • alimony paid
  • Keogh and IRA contributions
  • foreign income exclusion
  • NOLs
can be entered here as negative income.(+/-)
21. pensions Taxable Pensions and IRA distributions
22. gssi Gross Social Security Benefits
23. pui Unemployment Compensation received - primary taxpayer.
24 sui Unemployment compensation received - secondary taxpayer. The split is relevant only 2020-2021.
25. transfers Other non-taxable transfer Income that would affect eligibility for state property tax rebates but would not be taxable at the federal level, including:
  • welfare
  • workers compensation
  • veterans benefits
  • child support
26. rentpaid Rent Paid (used only for calculating state property tax rebates)
27. proptax Real Estate taxes paid. If itemized this is a preference for the AMT and is is also used to calculate state property tax rebates.
28. otheritem Other Itemized deductions that are a preference for the Alternative Minimum Tax. These would include
29. childcare Child care expenses.
30. mortgage Deductions not included above and not a preference for the AMT, including (on Schedule A for 2009)
  • Home mortgage interest (Line 15)
  • Deductible medical expenses not included in Line 16
  • Motor Vehicle Taxes paid (line 7)
  • Charitable contributions (Line 19)
  • Casulty or Theft Losses (Line 20)
The following are for the TCJA Business Tax Deduction.
but are ordinary income 1960-2017.
31. scorp S-Corp and other passive business income not subject to SSTB, SECA or QBID phaseout.
33. pbusinc Primary Taxpayer's active Qualified Business Income (QBI) subject to a preferential rate without phaseout and assuming sufficient wages paid or capital to be eligible for the full deduction. Subject to SECA and Medicare additional Earnings Tax.
34. pprofinc Primary Taxpayer's Specialized Service Trade or Business service (SSTB) with a preferential rate subject to claw-back. Subject to SECA and Medicare Additional Earnings Tax.
35. sbusinc Spouse's QBI. Must be zero for non-joint returns.
36. sprofinc Spouse's SSTB. Must be zero for non-joint returns.

OR...Upload a (not too large) file with TAXSIM data:

File to upload:
Marginal Rates (finite differences) with respect to: Other Income Wage Income Taxpayer Earnings Spouse Earnings Long Term Gains Other Deductions Dividends Mortgage Interest Don't bother
Show detailed intermediate calculations: Off On Labeled

Optional tax plan (leave blank)

Daniel Feenberg
1050 Mass Ave.
Cambridge MA 02138