For the past six months, one hypothesis has kept coming up in meetings with our investor buyers: rent controls will eventually be dropped, the ELAN experiment is drawing to a close, so one might as well build the yield on the rent the market will actually accept. That reading, long defensible, no longer holds.

Two recent events have closed the window. A prefectoral decree of 12 June 2026 set a new grid of reference rents, applicable in Paris until 24 November 2026. A ruling by the Paris tribunal judiciaire, handed down on 26 March 2026, ordered a landlord to repay more than five thousand euros in respect of a rent supplement annulled retroactively.

This edition is devoted to what these two texts change, in concrete terms, for a buyer considering letting out the property. The yield calculation now plays out within a narrower frame than it appears, and above all a more enforceable one.

Rent controls in Paris are no longer a political gamble, they are a calculation input

Many investor buyers still treat rent controls as a transitional constraint, tied to a political debate that could yet turn. A recent decree and a retroactive ruling have made that reading untenable.

The historical reflex was to calculate yield on the rent the Paris market was willing to pay, betting on three converging assumptions: the experiment would not be renewed, enforcement would remain weak, and the rent supplement would offer room to manoeuvre. All three assumptions are now weakened, separately and together. The experiment stemming from the ELAN Act of 23 November 2018, extended by the 3DS Act in February 2022, ends on 23 November 2026, and the debate is less about abandoning it than about a targeted extension.

The prefectoral decree of 12 June 2026 sets a new grid of reference rents in Paris, applicable from 1 July to 24 November 2026. The validity period is short, aligned with the national deadline, but the grid remains enforceable throughout that window. It covers all residential leases signed in Paris since 1 July 2019, whether unfurnished, furnished, in flatshares or under a bail mobilité. One point deserves attention: the signature date is what counts. A lease signed on 30 June 2026 and one signed on 1 July 2026 are not necessarily checked against the same grid.

What has shifted the equation, however, is not the decree. It is the ruling of 26 March 2026 by the Paris tribunal judiciaire. The judge annulled a monthly rent supplement of 356.38 euros and ordered the landlord to repay 5,702.08 euros in respect of sums unduly collected between September 2024 and December 2025. The court further held that a good DPE (energy rating) does not constitute an exceptional feature justifying a rent supplement, energy performance being already factored into the reference rent. Retroactive restitution changes everything: it makes betting on the future abandonment of the scheme costly, even if that bet were to prove right, since a sitting tenant can act on prior leases.

One figure is often cited to play down the risk: according to the data used by the evaluation mission entrusted to economists Gabrielle Fack and Guillaume Chapelle, delivered to the government on 22 May 2026, 35.6% of recent leases in Paris show a rent above the increased ceiling. This is sometimes read as de facto tolerance. The opposite reading imposes itself. That figure measures a stock of potential litigation, at a moment when the rent supplement is identified by the mission as the main vector for circumventing the scheme. For a buyer, sitting with the majority of landlords in breach is no longer a comfortable position, it is an exposure.

On the political front, the prospect of a clean exit is receding. In an interview with Le Monde published on 24 June 2026, Housing Minister Vincent Jeanbrun mentioned a two-year extension, reserved for communes already committed to the scheme. MP Iñaki Echaniz confirmed that the bill would be amended accordingly, to avoid a clean exit in November. Paris is among the communes concerned. The question is therefore no longer whether the scheme will apply in eighteen months' time, but which grid will apply and for how long.

The methodological consequence follows on its own. The rent ceiling, increased where applicable, becomes the low case of a serious business plan, not the pessimistic scenario in a range that would also feature a hoped-for market rent. The rent supplement, in turn, must be treated as a cautious variable: its justification must rest on genuinely exceptional features, documented, distinct from those already factored into the reference rent, failing which the three-month contestation window can be used by a well-informed tenant. On a Paris two-room flat financed at an average price of €9,580 per square metre, according to the Notaires du Grand Paris for the first quarter of 2026, a difference of ten euros or so per square metre per month between the initial assumption and the enforceable ceiling is enough to tip a net yield from accountant's figure to actual figure.

We refrain from predicting what the scheme will look like after November 2026. We merely observe that a Paris buy-to-let yield scenario which does not take the enforceable rent ceiling as its starting point, and which does not price in the risk of retroactive restitution on a poorly grounded supplement, now rests on a fragile implicit assumption. That framing is done before the offer, not after.

The rent supplement is documented at purchase, not at the lease

The features that may justify a rent supplement, ceiling height, private-use terrace, unobstructed view, rare heritage elements, are observed during viewings. We note them, photograph them and qualify them at the time of the property audit, so that the future landlord has a substantiated file if a tenant were to contest within the three-month window. A good DPE is not among them.

In the meantime, if a project is taking shape, we remain at your disposal for an initial conversation. We assess your brief against the market and deliver an unvarnished reading.