The global mergers and acquisitions market showed a significant resurgence in 2025, marking its second consecutive year of increased activity. Our research at WTW, conducted in partnership with the M&A Research Centre at Bayes Business School, reveals 726 deals completed in the last 12 months[1]. This 2% rise in volume for transactions valued over $100 million, compared to 710 in 2024, suggests a return to pre-pandemic levels of M&A engagement.
The aggregate performance gap between buyers and companies pursuing organic growth narrowed considerably in 2025. M&A transactions only marginally underperformed non-deal companies by -0.5 percentage points. This improvement is quite stark when compared to the previous year's underperformance of -10.9 percentage points. Furthermore, 32% of companies completing deals successfully outpaced the broader market, even with stock markets reaching record highs.
The total value of completed deals in 2025 climbed to $933 billion, an 11% increase from 2024. The continued rise in large transactions, those valued over US$1 billion, dominated M&A activity. We observed a 14% increase, with 201 completed deals compared to 177 in 2024. The average global size of these large M&A deals also reached a new high of $2.9 billion in the second half of 2025, representing a 23% year-on-year increase.
Large-scale deals are fueling the market, but they also carry significant risks and can make it challenging to protect and enhance value. Major investments based on a solid strategy have the power to transform a company and set the stage for long-term growth. However, deals that lack a clear, strategic purpose can quickly lead to the loss of value.
European dealmakers were the exception in 2025, outperforming their regional index by +4.7 percentage points, compared to +0.7 percentage points in 2024. They completed 153 deals, on par with the 155 that closed the previous year. British acquirers mirrored this trend, outperforming the index by +9.0 percentage points across 33 deals.
In contrast, Asia-Pacific buyers were -2.1 percentage points below their regional index, despite a 22% year-on-year deal volume increase with 199 completed deals. Chinese buyers, in particular, rebounded with 64 deals in 2025, up from a record low of 31 the previous year. North American acquirers underperformed by -1.5 percentage points with 348 deals, which is an improvement from -8.7 percentage points and 361 deals in 2024.
While 2025 saw an uptick in M&A activity, including a dramatically improved performance of +11 percentage points in Q3, dealmakers experienced a sharp reversal in the final three months. This period saw a record quarterly negative performance of -13.9 percentage points below the MSCI World Index.
Deal activity and overall optimism increased in 2025, driven by strong equity markets, relative economic stability, interest rate cuts, and a surge in AI adoption. Looking ahead, achieving the right scale will be crucial, as the market continues to favor larger companies that can withstand the sharp and unpredictable swings in M&A activity—now the 'new normal' for dealmakers facing ongoing geopolitical uncertainty.
Jana Mercereau is Head of Europe M&A Consulting. She has been working on deals since 2010 and has lead clients through major deals across all industries and all deal phases. She has been featured in The CFO, Reinsurance News, Commercial News and others for her insights and research in the M&A space.
David's a global leader in risk, broking and consulting. He has over 20 years of experience helping clients improve their business performance through effective people, risk and financial management. He is an expert in mergers and acquisitions, having rejoined the Global M&A team in 2022.
