Increase in the flat tax to 31.4% puts retirement savings plans under fiscal pressure

A Subtle Tax Mechanism at the Heart of the Reform

The adoption of the Social Security financing law for 2026 introduces a targeted increase in the CSG from 9.2% to 10.6%. This 1.4-point increase raises overall social levies from 17.2% to 18.6%, pushing the flat tax to 31.4% without changing the fixed income tax component at 12.8%.
This contribution, named CFA, is designed to fund the autonomy of the elderly through nursing homes and home care. It applies to capital gains, dividends, and interest, particularly in the context of an ordinary securities account (CTO) or a PEA. For a PER, the generated interest is fully impacted by this increase, as stipulated by the reform effective January 1, 2026. Investments such as life insurance or real estate are exempt from this measure, maintaining their relative attractiveness.
Investors in PER, who are often focused on a secure retirement, thus see their net returns reduced. On 10,000€ of interest, the tax increases from 3,000€ to 3,140€, or an additional 140€, a cost that accumulates over long-term horizons.

Retroactivity and Quantified Impacts on PERs

Gains realized in 2025, reported in 2026, are subject to the new rate of 31.4%, leading to criticism for retroactivity regarding capital gains and PER interest. Consequently, PER interest generated at the end of 2025 will incur a 31.4% tax rate during the declaration, compared to the initially expected 30%.
In practical terms, for €1,000 of PER interest, the tax burden increases to €314 instead of €300; for €50,000, it reaches €15,700 compared to €15,000, which is €700 more. On a PER accumulated over the years, this compounded effect impacts capitalization. Additionally, the period for deducting unused voluntary contributions extends from three to five years, providing contributors with more flexibility.
The increased social contributions, now at 18.6%, specifically affect investment income such as that from PER, without altering the tax brackets, which have been adjusted by 0.9% to counter inflation. This measure, combined with enhanced transparency through DAC8, encourages PER holders to exercise greater diligence in their 2026 declarations.

Adaptive Strategies for New Tax Policies

For PER savers with low tax burdens, opting for the progressive tax scale can be advantageous if their marginal rate is 0% or 11%, reducing the effective rate to 18.6% or 29.6% compared to the 31.4% flat tax. This alternative, declared at the time of tax choice, warrants a personalized simulation.
Regulated savings accounts (Livret A, LDDS, LEP) remain exempt, in contrast to the affected PER accounts.
Life insurance retains its unchanged regime, reinforcing its complementary role. For PERs, the increase does not affect deductible contributions during the savings phase, but it does increase the tax burden on annuities or lump sum withdrawals through taxed interest.
In a context of stable income tax brackets (0, 11, 30, 41, 45%), this adjusted social taxation encourages optimization of financial portfolios. Professionals recommend prioritizing contributions before the end of 2025 to limit exposure, while taking advantage of expanded deduction limits. A proactive management approach is essential to preserve retirement purchasing power.