According to Mundo Deportivo, Barcelona have around €60 million in financial fair play margin and are weighing a winter window signing against carrying the space into next season's salary cap.

The summer transfer window has just ended, but under Deco's leadership, Barcelona have already begun planning for the winter transfer window, which opens on January 2. The club currently have around €60 million in financial fair play margin, enough to complete a signing. However, the funds can also be used to increase next season's salary limit, and the return to the Luis Companys Olympic Stadium will have a major impact on that limit.
Barcelona failed to sign a left-footed centre-back before the summer window closed. If Deco believes it is necessary, the club could complete this signing in January.
Compared with June, Barcelona's financial fair play margin has not changed, as the amounts freed up by player departures and registration releases were basically offset by the spending on new arrivals.
However, Barcelona can also use their existing financial fair play margin to increase the salary limit for the 2027/28 season. Mundo Deportivo confirmed with people related to LaLiga that, according to note 7 of regulation article 44.4, Barcelona can apply to LaLiga to transfer the existing financial fair play margin into next season's salary limit, but two conditions must be met: the application must be submitted before the winter transfer window begins, and the amount transferred into the salary cap can only count as 75% of the planned transferred funds. If all of it is transferred, around €45 million can be included in the salary limit.

Because the roof installation at Spotify Camp Nou is ongoing, Barcelona will play at the Luis Companys Olympic Stadium for around four months before the 2027/28 season, meaning that season's salary limit will be lower than this season's. The club's income will decrease, and transferring the financial fair play margin into the salary limit can effectively offset the losses and allow them to remain within the 1:1 rule.
According to Barcelona data account "Gallinero Blau", Barcelona played the entire 2024/25 season at Montjuic and earned €175 million in revenue. This season, with all matches at Camp Nou, the club are expected to generate €290 million to €300 million in revenue.
On the other hand, once Camp Nou is fully reopened, the club's revenue will reach around €400 million. If Barcelona can return to Camp Nou in November, the 2027/28 season is expected to generate around €250 million in revenue, about €40 million less than this season.
Therefore, transferring the existing financial fair play margin into the 2027/28 salary limit can ease the impact of playing at Montjuic and would almost ensure Barcelona continue to comply with the 1:1 rule. However, the team would have no room for signings when the summer transfer window opens unless they first complete player sales.
The decision now rests with Barcelona: the club must either sign a player in January who can raise the team's ceiling, or transfer around €60 million of financial fair play margin into next season's salary limit to reduce the losses caused by playing at Montjuic and avoid breaching the 1:1 rule. Barcelona have less than three months to make a decision.