Tax · 6 min read · Updated 9 February 2026
Tax basics for retail investors: what to track from day one
You will not need this until next year, and by then it is too late to start. Here is what to record now.
This guide is general information, not tax advice. Rules vary by country and change often. Our country pages mention local specifics; a local accountant is the right person for your situation.
The three numbers most countries care about
- Realised capital gains and losses: the difference between what you paid and what you sold for
- Dividend and interest income, including interest paid on uninvested cash
- Foreign tax already withheld, which you may be able to offset
Broker with withholding versus self-reporting
Some domestic brokers calculate and pay tax for you. Foreign brokers usually do not, which means you must file. Neither is better; the withholding broker is simpler, the foreign broker may be cheaper.
What to download every year
- Annual statement of realised gains
- Dividend report with withholding tax
- Year-end holdings report
- Deposit and withdrawal history
This guide is general information, not financial, tax or legal advice.