Projects / Open Tax Solver

Open Tax Solver

OTS is an easy program for calculating personal income tax form entries and taxes-owed or refund due. It handles forms such as US-Fed-1040, with Schedules A, B, C, and D, forms 8829 and 8849, AMT worksheets, and state income taxes for several large states.

Operating Systems

Last announcement

User Survey Added to OTS Web site 21 Mar 2014 21:30

An anonymous user survey was added to the OpenTaxSolver web site to solicit feedback for improving OTS. If you use OTS, please drop by and fill out the survey.

Recent releases

  •  14 Apr 2014 19:05

    Release Notes: This revision updates the US-1040 AMT Part-III calculation section only.

    •  12 Feb 2014 03:29

      Release Notes: A new GUI for OTS was posted for downloading. The new GUI is based on Gtk, which offers an improved look and feel. It is now set as the default user interface in the regular OTS distribution package for Linux and Microsoft users. The older GUI is still included in case there are any problems with the new one. A user feedback survey was added to the webpage. The updated tax programs for this year remain stable.

      •  01 Feb 2014 11:58

        Release Notes: A fix was made for Line 27 of the US 1040 Qualified Dividends and Capital Gain Tax Worksheet in the US-1040 program. Additionally, some tool-tips, or hover-notes, were added in the OTS-GUI to provide hints about some of the button functions.

        •  25 Jan 2014 06:10

          Release Notes: The program was updated for the 2013 tax year. As in prior years, this version contains programs for US 1040 with Schedules A, B, C, D, and with the 8829 and 8849 forms. It also contains updated State versions for California, Pennsylvania, New Jersey, North Carolina, Ohio, Virginia, New York, and Massachusetts. Pre-compiled versions are available for Linux, Mac OS X, and MS Windows, along with source code.

          •  08 Apr 2013 02:43

            Release Notes: The initial version of OTS updated for the 2012 tax year has been released. It contains the US1040, with schedules A through D, along with forms 8829 and 8849. It also contains updated State Tax versions for Pennsylvania, New Jersey, Ohio, and Virginia. Pre-compiled versions were posted, along with sourcecode.

            Recent comments

            08 Jul 2012 22:20 fernandesc

            Please see sourceforge bugtracker for tgz attachment containing
            - README file with details
            - bugfix for NY IT201 itemized deduction worksheet calcs
            - new NY IT203 form
            - minor mod to US 1040 to calculate AMT lines 7 and 10
            - minor mod to ots_gui.c to display desired window width on startup, useful for repeated modify/restart debugging.

            I learnt that in order to display best in ots_gui, given that
            - it inserts page breaks as needed
            - overwrites multiple comments
            - does not handle multiline comments,
            you should arrange the input file as follows :

            Lxx {Description of Line xx provided by person who contributed the form}
   {description of the entry by the person filling out the form}
            ppp.qq {description of the entry by the person filling out the form}


            25 Feb 2012 00:06 aroberts

            Good catch krgkg ! Your fix was accepted and posted in version 9.01.

            09 Feb 2012 02:11 krgkg

            check this in the fed-1040

            L[42] = 3650.0 * L[6];

            should it be?

            L[42] = 3700.0 * L[6];
            sorry i can't file a bug report right now

            20 Jan 2012 08:15 aroberts

            Chris, yes sorry I had not replied to your earlier message. We are reviewing your IT-203 form for inclusion in the OTS package.
            -- Aston

            15 Jan 2012 01:59 fernandesc

            Hi Aston

            Hope this reaches you.

            I had emailed your yahoo account in Sept 2011 with patches for 2010 NYS IT- 203 (non-resident state form used by the nj bridge-and-tunnel crowd). Did not hear back, and took that to mean I should contact you on freecode instead of the address on the ots web page. So got my freecode login, but I still cannot see any developer discussions or details on how to submit. I'll admit I am new to this. I'm expecting that updating the NYS IT-203 will be easier than writing from scratch, so there is a good chance to get it done before Apr 17, far earlier than last year.

            Should I check in the 2010 changes on the sourceforge tracker:bugs?



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