// definition
Tax basis
Cost used to calculate a taxable gain
Short definition
The amount assigned to an asset or portfolio for tax purposes and deducted from disposal proceeds under the applicable rules to calculate a gain or loss. It tracks acquisitions, disposals and prescribed adjustments. Individual cost, weighted average cost and an allocated share of aggregate portfolio cost are methods whose scope must be established.
risk atlas
Knowledge map
Intuition
Basis already deducted on a disposal must be tracked when calculating later gains.
Why it matters now
The investigation compares France’s current regime with a proposed change to cost calculations and carryover rules under amendment I-3898.
Related analyses
Primary sources
- French tax administration, crypto-asset capital gains tax baseAggregate portfolio cost and basis previously deducted, paragraphs 1 and 70 to 110.
- National Assembly, amendment I-3898Asset-level cost, weighted averages and transition rules proposed in an adopted amendment; the legislative process remains ongoing.