Hi all,
I've finally cleaned up code I wrote for UK capital gains tax reporting: GitHub - Evernight/beancount-plugin-tax-uk: Beancount plugin for generating informational UK tax report.
The usual disclaimer: I'm not an accountant, tax specialist or a finance expert. Use this code for informational purposes and at your own risk and without any guarantees. More so, at this starting point it's more of an RFC since there are some test cases known not to be handled correctly. I'll fix at least some of them later. More generic simpler cases are expected to work though.
There have been some discussions here [beancount] Status of the "improved inventory booking" proposal?, [repost] Example: calculating UK capital gains with ledger (ledger-related), https://groups.google.com/g/beancount/c/F6rc8QgTNEY and in other places regarding average cost booking implementation which does not exist yet (as far as I know). The plugin, perhaps, does not implement it in the most native way, instead externalising all the calculations. However, it takes into account specific UK rules (S104, same day, bed&breakfast) that would have to be handled manually even if the average cost booking was implemented directly in Beancount, so it's better specifically for the UK in some ways.
Please take a look if this is something relevant for you, feel free to create an issue or contribute test cases and code.
Cheers,
Vasily