How does MD calculate cost basis

retail's Avatar


23 Jul, 2023 06:50 PM

I've read through many posts related to Moneydance and cost basis. Other than the apparent consensus that MD's calculation of cost basis is somewhat iffy, I've not gotten a clear picture of exactly where the underlying issues are. If I've missed this question already answered in a previous thread, lease excuse the duplication.

To get at the root of my problem, I'll focus on only the very first two transactions.

I purchased 600 shares of MySecurity for a $24,486 on 11/18/2022 with a per share cost of $40.81. I received a dividend on 12/15/2022 of $42.32 and it was automatically reinvested at $41.05 per share resulting in 1.031 additional shares.

On 12/31/2022, my institution says I held 601.031 shares with a cost basis of $24,527.05.
On 12/31/2022, my Moneydance portfolio report says I have 601.031 shares with a cost basis of $9,225.

What could possibly cause these two figures to be so drastically different?


  1. 1 Posted by Stuart Beesley ... on 23 Jul, 2023 10:48 PM

    Stuart Beesley (Mr Toolbox)'s Avatar

    Well… the MD CB calculation does (can) work just fine. So we should start with what your txns in MD looked like?

    Can you send a SS of both, and also whether you are using average cost basis, or lot control?

  2. System closed this discussion on 22 Oct, 2023 10:50 PM.

  3. Stuart Beesley (Mr Toolbox) re-opened this discussion on 24 Feb, 2024 09:32 AM

  4. 2 Posted by Stuart Beesley ... on 24 Feb, 2024 09:32 AM

    Stuart Beesley (Mr Toolbox)'s Avatar

    You don’t say if this is average cost or lot control and also whether splits are involved.

    I would be interested to see a screenshot of the txns and also whether the portfolio screen. Portfolio report or cost basis reports calculations are the same and / or right/we

  5. 3 Posted by Stuart Beesley ... on 04 Apr, 2024 10:27 AM

    Stuart Beesley (Mr Toolbox)'s Avatar

    FYI. The cost basis / gains engine has been rewritten for the latest Alpha MD2024(5101)

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