Every year, taxpayers seek to optimize their situation when declaring their taxes. A largely ineffective reflex: expenses allowing the reduction of the tax declared in 2026 were, for the most part, carried out in 2025. The declaration therefore mainly serves to arbitrate: checking the boxes, choosing between several tax options and avoiding oversights which can increase the bill.
For Claire Guenault, independent asset manager, everything is based on an essential distinction. “There are three main mechanisms: tax deductionthere rtax reduction and the tax credit “. A deduction reduces taxable income (like the PER), a reduction directly reduces the tax payable (such as donations), while a tax credit can be reimbursed, even if you are not taxable, reminds Bercy.
PER, real costs: accessible but often poorly understood levers
THE PER remains the most widespread reflex. Payments are deductible from taxable income, within the limit of a ceiling indicated on your tax noticegenerally close to 10% of professional incomeaccording to Service-Public.fr.
But be careful of the misleading effect. “The PER is only of interest in a tax optimization framework”, insists Claire Guenault. This product, widely distributed by banks and insurers, is often presented as a universal solution, when in reality it is only aimed at certain tax profiles. Without high taxation, the gain is low, while savings remain blocked until retirement and will be taxed upon exit.
Another simple and often neglected lever: the choice between 10% reduction And actual costs. “People forget it, but declaring your real expenses can be enough to reduce your tax “. Business travel, meals or teleworking: when expenses exceed the allowance, the impact is immediate.
Donations, tax credit: simple and immediate solutions
Certain measures allow you to reduce taxes directly, without a complex strategy. THE donations to associations entitle you to a tax reduction of 66% to 75% of the amount paid, according to the organization (economie.gouv.fr). An accessible lever, even for modest amounts.
“Many people do nothing because they don’t know about the systems… even though you can invest for yourself while serving the community,” underlines the advisor.
Concretely, a parent can, for example, support their child’s sports association, finance materials or equipment, and benefit from a tax advantage, subject to respecting the rules.
Another very effective lever: the tax credit for working from homewhich allows you to recover 50% of expenses incurredwithin the limits of the ceilings in force. Unlike a reduction, this credit can be reimbursed even without tax payable.
Girardin: a powerful lever but reserved for experienced profiles
More technical, the device Industrial Girardin allows you to significantly reduce your tax by investing in overseas projects. This type of arrangement, often unknown to the general public, remains mainly used by the highest taxed taxpayers.
“These are systems which require liquidity and which are aimed at highly taxed taxpayers”, specifies Claire Guenault.
Concrete example: “You pay 15,000 euros in taxes. You invest 12,195 euros in the device. The State considers that you have “advanced” your tax and returns it to you 2,805 euros “.
In other words, the tax is transformed into investment, with a immediate tax gain. But these arrangements remain regulated and carry risks. “We must understand the mechanism: we do not eliminate the tax, we pay it differently.”
Last minute: “it’s too late” in most cases
Once the declaration is opened, the room for maneuver is limited. “People contact me saying: I’m going to pay a lot, what can I do? The answer is simple: nothing. It’s too late”says Claire Guenault.
The right timing is upstream, ideally before the end of the year.
In practice, the most accessible levers remain the actual costsTHE donations and the tax credits. More complex devices, such as Girardinshould be reserved for informed profiles. Reducing your tax is not about increasing the number of measures, but about using the right ones, at the right time, and above all for the right reasons.
