Behind every headline transfer fee in football lies a web of conditional payments that can significantly alter the final cost of a deal. These so-called add-ons, or performance-related clauses, have become a standard feature of modern transfer negotiations, and their scale can be substantial, as recent financial disclosures from Manchester United illustrate.
In United's third-quarter financial results for the 2024-25 season, published on 6 June, the club revealed details of these obligations buried deep within a 47-page report. On page 45, United acknowledged that under agreements with various clubs and agents, additional sums beyond the initial transfer fees could become payable if specific performance benchmarks are met.
According to the filing, United's potential liability from such add-ons stood at £138.82m as of 31 March 2025. The breakdown shows £112.25m tied to factors such as player appearances, team success, or the signing of new contracts. A further £3.19m relates to international appearances, while £22.03m is connected to individual awards. The remainder falls under a broader 'other' category.
These figures highlight just how significant add-ons can be in shaping the true cost of a transfer, often making headline fees only part of the overall financial picture. Clauses can be linked to a wide range of achievements, from a certain number of appearances to trophies won, and even prestigious individual honors.
One notable example from United's past dealings involved Anthony Martial's £36m move from Monaco. At the time of his transfer, the club disclosed that part of the agreement included a clause connected to the France international potentially winning the Ballon d'Or. That condition was never triggered, as Martial did not reach that level of individual recognition during his time at Old Trafford.
Such clauses, while ambitious, are not unusual in high-profile transfers, particularly for young talents seen as having significant potential. Clubs selling players often negotiate these add-ons as a way to benefit further down the line if the player fulfills expectations that justify a higher valuation than initially agreed.
Another case that drew scrutiny involved Mason Mount, who joined United from Chelsea. Speculation arose over whether his participation in a European final for United—the Europa League final defeat to Tottenham—might have triggered one of the add-ons included in his transfer agreement. United moved quickly to dismiss these claims, denying that the clause had been activated by that specific event.
The Martial case, in particular, underscores the complexity of such arrangements. Winning the Ballon d'Or is an extraordinarily difficult achievement, reserved for only the very best players in the world in a given year. Despite the seemingly unlikely nature of the clause, United reportedly maintained that had Martial reached that pinnacle of individual success, they would have been more than willing to honor the payment, given the on-field benefits such a level of performance would have brought to the club.
These examples reveal the intricate financial mechanics that underpin modern football transfers, extending far beyond the simple published fees that often make headlines. As clubs continue to navigate a competitive market, add-ons remain a common tool used to balance risk and reward between buying and selling clubs, with performance-based incentives designed to align the interests of both parties.
Based on reporting from BBC Sport.