Data from WTW's Quarterly Deal Performance Monitor reveals that completed M&A deal value grew by 23.9% year-on-year during the first nine months of 2026, rising to $1.65bn from $1.33 bn in the same period of 2025.
Mega deals valued at over $10bn delivered their strongest nine-month start to a year, with 24 completed transactions surpassing the highs of the previous boom, WTW’s Quarterly Deal Performance Monitor noted.
According to WTW data produced in partnership with the M&A Research Centre at Bayes Business School, this also represents the largest nine-month rolling period on record. Momentum accelerated in the most recent quarter, with nine mega deals completed, up sharply from three in the previous quarter.
Reported year-to-date deal volume rose to 614, up from 529 transactions completed during the same period in 2025, representing a 16.1% increase. However, the number of large transactions (valued between $1bn and $10bn) softened in the third quarter of 2026, declining to 45, from 48 in the previous quarter. Overall deal volume also eased slightly at 200 transactions, compared with 202 during the same period.
The M&A data also indicates that dealmakers are accelerating transaction timelines, with quick deals (completed within 70 days of announcement) accounting for 43% of third-quarter transactions, up from 35% in the previous quarter. Over the same period, complex cross-sector deals, often pursued to support rapid inorganic growth or embed new technologies, rose to 35% of transactions, compared with 25% in the previous three months.
Of the 200 deals completed during the most recent quarter, 121 transactions, representing 60.5%, underperformed the index, while 79 acquirers, or 39.5%, outperformed.
Based on share price performance, global dealmakers underperformed companies not engaged in M&A for the second consecutive quarter. Deals valued above $100m and completed during the past three months underperformed the index by 10.3 percentage points (pp).
Regional performance remained under pressure in the third quarter of 2026, with acquirers in North America, Europe and APAC all underperforming their respective regional indices.
Acquirers in APAC underperformed their regional index by 18.7pp in 3Q2026, completing 43 deals compared with 51 in the previous three-month period. Chinese buyers, however, recorded a notable increase in activity, completing 21 deals, up from seven in the second quarter of 2026.