Withholding at source was judged “necessary and successful” by the Court of Auditors. In the same year, the tax administration received 2.7 million more calls. Both are true—and the second line reveals something the first does not.
On January 1, 2019, income tax began to be deducted monthly directly from salaries and pensions. The one-year delay, the provisional third payments, and the white year for those who retire were over. In principle, no one regrets it: a year after the switch, nearly 81% of taxpayers did not want to return to the former system.
And yet, in that very first year, the counters, the standard offices, and the mailboxes of the Directorate General for Public Finances were overwhelmed. The figure is in the Court of Auditors’ January 2022 report: between 2018 and 2019, nearly 2 million more emails were sent to the tax administration and 2.7 million more phone calls addressed to it.
Why call a massively an administration whose reform is approved? The answer lies in a calendar detail that very few taxpayers anticipated.
The 2019 rate was calculated on 2017 income
That is the blind spot of the reform, and it has a very concrete consequence. Between January and September 2019, the rate applied to payrolls was calculated from the 2018 filing, which concerned the 2017 income. The rate was only updated in September, after the spring declaration.
In other words: a taxpayer whose income had fallen in 2018 — move to part-time, end of contract, retirement, separation — was taxed for nine months on a level of income they no longer had. The overpayment would be refunded to them, but not before 2020. The point was raised by a written question in the National Assembly (no. 24064, Christophe-André Frassa / Michel Parigi): the withholding could exceed what was actually due, with a refund deferred to the following year.
This mechanism was not a mistake. It was the logical consequence of moving from one system to another, and it was correctible: anyone could request a modulation of their rate during the year. It was just necessary to know that it existed. That is exactly what the call curve shows.
What the reform cost the State
The cost of the switch for the tax administration amounts to €214.6 million, mainly investments in information systems. The Court of Auditors does not present it as a drift: on the contrary, it hails a favorable cost-benefit ratio, and describes the entire effort as a “necessary and successful reform.”
Let’s state it clearly, because the figure often circulates detached from its verdict: €214.6 million to overhaul the collection of income tax for all French tax households, with 1.9 million companies and nearly 74,000 public entities or pension funds transformed into collectors, is not the budgetary scandal one might imagine. It is a heavy IT investment for a machine that, technically, held up from the first month.
The problem is not there. It lies in what no one had budgeted: the need to talk to someone.
The service degraded at the moment when you needed it most
The figures for the first quarter of 2019 measure the wave. In just those three months, the special toll-free line dedicated to the reform received 2.2 million calls, to which were added three million visits to the counters and nearly 300,000 email requests.
Meanwhile, the traffic on impots.gouv.fr had already surged by 39% as early as 2018. The digital channel thus absorbed a substantial portion of demand—but not all. And for those who needed an interlocutor, the Court notes a deterioration in response times by mail and by phone during 2017-2020.
That is the real issue, and it is more troubling than the sheer volume of calls: the reform created a spike in the need for human explanations at the exact moment when the administration was reducing its capacity to provide them.
A note of honesty is due here, and it comes from the Court itself: it acknowledges it cannot establish a true quantified assessment of users’ inquiries, due to the lack of a complete tally of calls and letters received by local services before 2020. The 2.7 million additional calls are therefore an order of magnitude, not a precise accounting. The Court also recommended in 2021 to the DGFiP to strengthen the tracking of taxpayers’ questions by broadening it to all contact channels — which amounts to saying that in 2019 the State did not know how to measure precisely the distress it had produced.
What the 2020 crisis proved
The following year served as a real-life test. Faced with the sudden collapse of income for millions of households in spring 2020, withholding at source allowed the tax to be adjusted in real time, without waiting for a regularization a year later. Under the old system, households would have paid in 2021 a tax calculated on a 2019 year that bore little relation to their situation.
That is the strongest argument for the system, and it is rarely highlighted: the value of withholding at source does not appear when everything goes well, it shows up when life takes a turn. In the wake of this, the automatic filing, launched in 2020 for nearly 12 million households, removed any need for actions in the simplest situations.
What remains to be done, and which concerns you today
Seven years on, the mechanism is well-tuned, but one reflex never took hold: the modulation of the rate. The rate currently applied on your paycheck or pension derives from your most recent filing. If your situation has changed since — reduced activity, retirement, widowhood, separation, long-term absence — it will not adjust by itself until the next update.
That is exactly the 2019 problem, but more discreet: we keep paying on an old snapshot, and the money returns later. It is not lost—it simply sits elsewhere than in your account, sometimes for more than a year.
The lesson of the Court of Auditors’ report is therefore not that the reform failed. It succeeded. It shows that a reform can be technically impeccable and leave millions of people without an answer to a simple question: Why this amount, on my own line?
Sources : Court of Auditors, The contributions of withholding at source on income tax, January 2022 — Senate, report on access to public services, 2024-2025 — National Assembly, written question no. 24064 — economie.gouv.fr, impots.gouv.fr
