Box 2OP: tick it or not? Flat tax vs scale, the real math
By default, your dividends and interest face the flat tax (12.8% income tax + 17.2% social levies). Ticking box 2OP switches them to the progressive scale: a win if your bracket is 0% (you save 12.8% of the amount) and often at 11%, a loss at 30% and above.
What box 2OP changes
Box 2OP (form 2042, investment-income section) replaces the 12.8% flat tax with the progressive scale on ALL your year’s capital income — dividends, interest, and also your securities capital gains. It’s a global choice: you can’t pick line by line.
Under the scale, dividends regain the 40% allowance and part of the CSG becomes deductible — which is why the option often wins in the 11% bracket, especially for dividends.
The simple rule by bracket
0% bracket (low taxable income): tick — the gain is exactly 12.8% of your capital income.
11% bracket: often a win — about 6.9% saved on dividends, 2.5% on interest (the gap comes from the 40% allowance reserved for dividends).
30% bracket or above: do NOT tick — the scale would cost you more than the flat tax.
Careful: once ticked, the box is sometimes carried over automatically the following year. Check it at every return, especially if your income went up.
Your personalized verdict, with numbers
The “Income tax return (2042)” flow asks your bracket and the nature of your capital income, then gives you the 2OP verdict with the estimated saving in euros — not just “it depends”.
Frequently asked questions
How do I know my bracket?
Your marginal rate appears on your last tax assessment. As an order of magnitude: with no other income, a single person enters the 11% bracket above roughly €11,500 of taxable income, and the 30% bracket above roughly €29,000.
Does 2OP affect my PEA?
No — gains inside a PEA follow the PEA’s own regime. 2OP concerns taxable capital income outside wrappers (ordinary securities account, non-regulated savings, directly received dividends…).