Global mergers and acquisitions (M&A) activity increased in the first nine months of 2026, with higher-value transactions contributing to a rise in overall deal value, according to WTW, the global professional services company providing risk, insurance, investment and consulting services.
WTW reported that the value of completed M&A transactions rose by 23.9% during the first nine months of 2026, increasing from USD $1.33 billion in the same period of 2025 to USD $1.65 billion. The figures are from WTW’s Quarterly Deal Performance Monitor (QDPM), produced in partnership with the M&A Research Centre at Bayes Business School.
According to WTW, the increase was partly driven by a rise in transactions valued at more than USD $10 billion. Twenty-four mega deals were completed during the first nine months of the year, representing the strongest nine-month period recorded for transactions of this size.
WTW reported that activity accelerated during the third quarter, with nine mega deals completed compared with three in the previous quarter. The company said the latest nine-month period also represented the largest rolling nine-month total on record.
The number of completed transactions increased overall. WTW recorded 614 deals during the first nine months of 2026, compared with 529 during the same period in 2025, an increase of 16.1%.
Activity among deals valued between USD $1 billion and USD $10 billion was more subdued. WTW recorded 45 transactions in this category during the third quarter, down from 48 in the previous quarter. Total deal volume also edged down, with 200 transactions completed during the quarter compared with 202 in the preceding three months.
WTW’s research indicates that some transactions are also being completed more quickly. Deals completed within 70 days of announcement accounted for 43% of third-quarter transactions, compared with 35% in the previous quarter.
The proportion of cross-sector transactions also increased. WTW reported that these deals represented 35% of transactions during the third quarter, compared with 25% in the previous three months. Such transactions can involve companies seeking to expand into new areas, support inorganic growth or acquire technology capabilities.
Jana Mercereau, Head of Europe M&A Consulting at WTW, commented: “Mega deals continue to reshape the global M&A landscape, as companies move decisively to build scale, close capability gaps and secure critical technologies in an increasingly competitive market.
“While faster deal execution reflects the increasingly dynamic nature of today’s M&A environment, shaped by AI-driven transformation, geopolitical tensions and macroeconomic uncertainty, speed must not come at the expense of rigorous due diligence. Companies that prioritise pace over discipline risk undermining long-term value creation and increasing the likelihood of post-closing challenges.”
Despite the increase in transaction values, WTW found that the majority of acquiring companies completing deals during the third quarter underperformed their relevant market indices. Of the 200 transactions recorded, 121 acquirers, or 60.5%, underperformed, while 79, equivalent to 39.5%, outperformed.
WTW’s analysis compares the share price performance of acquiring companies with the MSCI World Index unless another benchmark is specified. For transactions valued above USD $100 million and completed during the third quarter, acquiring companies underperformed the index by 10.3 percentage points.
Regional results varied during the quarter. North American acquirers completed 109 transactions, compared with 103 in the previous three months, but underperformed their regional index by 13.8 percentage points, according to WTW.
European acquirers completed 37 transactions during the third quarter and underperformed their regional index by 5.0 percentage points. WTW said European deal volume has fallen for four consecutive quarters, from 47 transactions in the third quarter of 2025. UK buyers, however, recorded an outperformance against the wider regional trend.
Asia-Pacific acquirers completed 43 transactions during the quarter, down from 51 in the previous three months, and underperformed their regional index by 18.7 percentage points.
WTW also recorded increased M&A activity among Chinese buyers. Chinese acquirers completed 21 transactions during the third quarter, compared with seven in the second quarter of 2026.
Mercereau added: “Corporate buyers continue to show remarkable resilience despite persistent market headwinds. Even amid rising interest rates, surging energy costs and November’s US midterm elections, dealmakers are expected to press ahead with strategic transactions, particularly at the upper end of the market.
“As more companies pursue scale, early integration planning during the due diligence phase will be critical to capturing value from complex deals and driving long-term, sustainable growth.”
WTW’s Quarterly Deal Performance Monitor covers completed M&A transactions valued at more than USD $100 million and assesses the share price performance of acquiring companies against the MSCI World Index, unless otherwise stated.
