HolderTax · Status: working draft · every figure awaits sign-off by a licensed reviewer · not tax, legal or investment advice
HolderTax / France / Rules / Flat tax & formula
Rule explainer · France · Schedule lines 02, 03, 06–08

The flat tax and the global portfolio formula

Two things set France apart: a rate that just moved from 30 to 31.4%, and a computation unlike any other — no FIFO, no lots, but a fraction of invested capital released at every disposal, computed on the value of your entire portfolio that day.

Working draft · mechanics pending sign-off by a licensed reviewer · not advice on your computation

The rate: 31.4% — and why it moved

The flat levy on digital-asset gains stands at 31.4% since 1 January 2026: 12.8% income tax plus 18.6% social levies, after the CSG on capital income rose from 9.2 to 10.6%. Gains realised through 31 December 2025 — declared in spring 2026 — stayed at 30%. The lesson outweighs the number: the "flat" rate moves with each finance act, and we keep this line on watch. The progressive-scale option, open since 2023, replaces the 12.8% income-tax leg — worth computing in the 0 and 11% brackets, rarely above.

The formula: a fraction of capital, not a lot

The taxable gain on a disposal is: disposal price − (total acquisition cost of the portfolio × disposal price ÷ global portfolio value on the day of disposal). In plain terms: sell 10% of your portfolio's value and you "consume" 10% of all the capital you ever put in — every coin, every platform, every wallet combined. There is no FIFO and no lot-picking: the portfolio is one whole, and every taxable disposal requires knowing its total value that day.

Germany tracks every coin to the day; France tracks a single number — but demands it for everything you own, at every sale. Two irreconcilable ledgers: a foreign FIFO tax report does not convert, it recomputes.

The three numbers that frame it

€305: if your total taxable disposals for the year stay under this, the exemption is complete — but it reads amounts sold, not gains: selling €1,000 with a €50 gain makes those €50 taxable. One year: losses offset digital-asset gains of the same year, and the excess dies — no carryforward. Realising a loss in December with no gain to absorb it is realising it for no one. Ten years: the administration's assessment window when foreign holdings went undeclared — line 11 weighs on this one.

What stays open

How staking rewards and airdrops are classified on receipt is not uniformly settled — non-commercial business income for some, investment income or zero-cost portfolio entry for others. We mark the line "?": the position is chosen with advice and documented, not improvised in a form box. And activity run in professional conditions — tooling, complexity, leverage — falls into business income since 2023: the boundary follows the conditions of trading, not the order count.

What to do

  1. Keep the full acquisition history — from the beginning. The formula needs the portfolio's total acquisition cost: every buy, every platform, every year still counts.
  2. Photograph the portfolio at every taxable disposal. Global value on the day of sale, one stable price source — the variable no one reconstructs from memory.
  3. Synchronise losses and gains within the year. With no carryforward, a loss only counts if a same-year gain absorbs it.
  4. Compute the progressive option before ticking it. It binds the year; in low brackets it wins, elsewhere it costs.