MarketAxess Holdings Inc. (Nasdaq: MKTX), the operator of a leading electronic trading platform for fixed-income securities, today announced trading volume and preliminary variable transaction fees per million (“FPM”) for December 2025 and the fourth quarter ended December 31, 2025.1 Select Fourth Quarter 2025 Highlights* (See tables 1-1C and table 2) Our new initiatives continued to show strong year-over-year progress across the client-initiated, portfolio trading and dealer-initiated channels. Client-Initiated Channel 29% growth in block trading average daily volume (“ADV”), with strong growth across U.S. credit (+21%), record emerging markets (+41%) and eurobonds (+43%). Portfolio Trading Channel 41% increase in total portfolio trading ADV to a record$1.5 billion, with record U.S. high-yield portfolio trading ADV of $368 million and record emerging markets portfolio trading ADV of $118 million. Our estimated market share of U.S. credit portfolio trading was a record20.6%, compared to 16.2% in the prior year, and 19.1% in 3Q25. Record U.S. credit portfolio trading estimated market share in the quarter was driven in part by record U.S. high-yield estimated market share in December 2025 of 27.7%. Dealer-Initiated Channel 32% increase in dealer-initiated ADV to $1.8 billion, consisting of a 20% increase in Dealer RFQ ADV and an 185% increase in Mid-X ADV. Our Mid-X protocol in U.S. credit surpassed $3.0 billion in trading volume in December 2025. Fourth Quarter 2025 Variable Transaction Fees Per Million1 (See table 1D) The decline in total credit FPM both year-over-year and quarter-over-quarter was driven principally by protocol mix, partially offset by the higher duration of bonds traded in U.S. high-grade. Total credit FPM in December 2025 was flat month-over-month compared to November 2025. The increase in total rates FPM both year-over-year and quarter-over-quarter was driven by the impact of product mix. *All comparisons versus fourth quarter 2024 unless noted. Table 1: MarketAxess ADV   Month % Change Quarter % Change     Dec-25   Nov-25   Dec-24   MoM YoY   4Q25   3Q25   4Q24   QoQ YoY MKTX ADV ($ millions)                                                 Credit                                                 U.S. High-Grade (incl. SD PT)2   $ 6,275   $ 7,763   $ 5,949     (19 ) % 5   %   $ 7,035   $ 6,783   $ 6,578     4   % 7   % U.S. High-Grade (excl. SD PT)2     6,043     7,594     5,921     (20 )   2         6,848     6,558     6,454     4     6     U.S. High-Yield (incl. SD PT)2     1,591     1,791     1,222     (11 )   30         1,749     1,557     1,378     12     27     U.S. High-Yield (excl. SD PT)2     1,391     1,622     1,219     (14 )   14         1,543     1,347     1,345     15     15     Emerging Markets     3,515     4,265     2,869     (18 )   23         3,986     3,803     3,459     5     15     Eurobonds     2,003     2,741     1,619     (27 )   24         2,407     2,196     2,001     10     20     Other Credit Products3     594     586     657     1     (10 )       597     631     624     (5 )   (4 )   Municipal Bonds     593     585     656     1     (10 )       597     630     620     (5 )   (4 )   Total MKTX Credit ADV (excl. SD PT)2   $ 13,546   $ 16,808   $ 12,285     (19 )   10       $ 15,381   $ 14,535   $ 13,883     6     11     Rates                                                 U.S. Government Bonds   $ 19,406   $ 22,966   $ 18,735     (16 ) % 4   %   $ 21,819   $ 23,130   $ 25,952     (6 ) % (16 ) % Agencies and Other Government Bonds     620     715     1,017     (13 )   (39 )       686     1,166     1,195     (41 )   (43 )   Total MKTX Rates ADV   $ 20,026   $ 23,681   $ 19,752     (15 )   1       $ 22,505   $ 24,296   $ 27,147     (7 )   (17 )   Total MKTX Trading ADV   $ 33,572   $ 40,489   $ 32,037     (17 )   5       $ 37,886   $ 38,831   $ 41,030     (2 )   (8 )   U.S. Trading Days4   22   18   21               62   64   62             U.K. Trading Days4   21   20   20               64   65   64             Table 1A: Market ADV   Month % Change Quarter % Change     Dec-25   Nov-25   Dec-24   MoM YoY   4Q25   3Q25   4Q24   QoQ YoY MARKET ADV ($ millions)                                                 Credit                                                 U.S. High-Grade TRACE   $ 32,493   $ 41,114   $ 30,344     (21 ) % 7   %   $ 37,240   $ 37,028   $ 34,986     1   % 6   % U.S. High-Yield TRACE     10,112     12,279     8,294     (18 )   22         11,563     11,348     10,061     2     15     Total U.S. Credit TRACE     42,605     53,393     38,638     (20 )   10         48,803     48,375     45,047     1     8     Municipal Bonds MSRB     9,555     9,457     9,630     1     (1 )       9,686     10,908     8,755     (11 )   11                                                       Rates                                                 U.S. Government Bonds TRACE   $ 944,841   $ 1,091,150   $ 832,181     (13 ) % 14   %   $ 1,006,294   $ 1,006,577   $ 926,037     (0 ) % 9   % Agency TRACE     3,454     3,449     3,294     0     5         3,548     4,177     3,897     (15 )   (9 )   U.S. Trading Days4   22   18   21               62   64   62             U.K. Trading Days4   21   20   20               64   65   64             Table 1B: Estimated Market Share     Month   Bps Change   Quarter     % Change     Dec-25     Nov-25     Dec-24   MoM YoY   4Q25     3Q25     4Q24     QoQ YoY MKTX ESTIMATED MARKET SHARE (%)                                           U.S. High-Grade                                           % of U.S. High-Grade TRACE (incl. SD PT)2   19.3 %   18.9 %   19.6 % +40 bps (30) bps   18.9 %   18.3 %   18.8 %   +60 bps +10 bps % of U.S. High-Grade TRACE (excl. SD PT)2   18.6 %   18.5 %   19.5 % +10   (90)     18.4 %   17.7 %   18.4 %   +70   -   U.S. High-Yield                                           % of U.S. High-Yield TRACE (incl. SD PT)2   15.7 %   14.6 %   14.7 % +110 bps +100 bps   15.1 %   13.7 %   13.7 %   +140 bps +140 bps % of U.S. High-Yield TRACE (excl. SD PT)2   13.8 %   13.2 %   14.7 % +60   (90)     13.3 %   11.9 %   13.4 %   +140   (10)   Other Credit Products                                           % of Municipal Bonds MSRB   6.2 %   6.2 %   6.8 % - bps (60) bps   6.2 %   5.8 %   7.1 %   +40 bps (90) bps Rates                                           % of U.S. Government Bonds TRACE   2.1 %   2.1 %   2.3 % - bps (20) bps   2.2 %   2.3 %   2.8 %   (10) bps (60) bps Table 1C: Strategic Priorities ADV2     Month   % Change   Quarter   % Change     Dec-25   Nov-25   Dec-24   MoM YoY   4Q25   3Q25   4Q24   QoQ YoY STRATEGIC PRIORITIES ADV ($ millions)                                                 Client-Initiated Channel                                                 U.S. Credit Block Trading   $ 2,298   $ 3,245   $ 2,108     (29 ) % 9   %   $ 2,811   $ 2,589   $ 2,330     9   % 21   % Emerging Markets Block Trading     1,494     1,954     1,004     (24 )   49         1,687     1,553     1,194     9     41     Eurobonds Block Trading     291     532     195     (45 )   49         425     364     297     17     43     Portfolio Trading Channel                                                 Total MKTX Portfolio Trading   $ 1,541   $ 1,364   $ 1,002     13   % 54   %   $ 1,491   $ 1,375   $ 1,060     8   % 41   % Total MKTX U.S. Credit Portfolio Trading     1,200     1,003     825     20     45         1,146     1,140     796     1     44     Total U.S. Credit TRACE Portfolio Trading     5,206     5,685     4,950     (8 )   5         5,555     5,962     4,929     (7 )   13     Dealer-Initiated Channel                                                 Total Dealer Initiated (DRFQ & Mid-X)   $ 1,602   $ 1,916   $ 1,088     (16 ) % 47   %   $ 1,755   $ 1,516   $ 1,334     16   % 32   % Other                                                 Open Trading   $ 4,382   $ 5,370   $ 3,642     (18 ) % 20   %   $ 4,939   $ 4,349   $ 4,130     14   % 20   % AxessIQ     160     170     135     (6 )   19         164     163     147     1     12     U.S. Trading Days4   22   18   21               62   64   62             U.K. Trading Days4   21   20   20               64   65   64             Table 1D: Variable Transaction Fees Per Million (FPM)1     Month   % Change   Quarter   % Change     Dec-25   Nov-25   Dec-24   MoM YoY   4Q25   3Q25   4Q24   QoQ YoY AVG. VARIABLE TRANS. FEE PER MILLION (FPM)                                             Total Credit   $ 138   $ 138   $ 148     0   % (7 ) %   $ 138   $ 140   $ 150     (1 ) % (8 ) % Total Rates     4.79     4.52     4.14     6     16         4.72     4.21     4.31     12     10     1 The FPM for total credit and total rates for December 2025 and 4Q25 is preliminary and may be revised in subsequent updates and public filings. The Company undertakes no obligation to update any fee information in future press releases. 2 “SD PT” is defined as single-dealer portfolio trades. The Company is currently highlighting the impact of single-dealer portfolio trading volume on U.S. high-grade and U.S. high-yield trading volume and estimated market share, but will continue to exclude single-dealer portfolio trading activity from each product’s aggregated trading volume and estimated market share and the total credit FPM calculation. 3 “Other Credit Products” includes municipal bonds, leveraged loans, convertible bonds and structured products. 4 The number of U.S. trading days is based on the SIFMA holiday recommendation calendar and the number of U.K. trading days is based primarily on the U.K. Bank holiday schedule. General Notes Regarding the Data Presented Reported MarketAxess volume in all product categories includes only fully electronic trading volume. MarketAxess trading volumes and the Financial Industry Regulatory Authority (“FINRA”) Trade Reporting and Compliance Engine (“TRACE”) reported volumes are available on the Company’s website at investor.marketaxess.com/volume. Table 2: Trading Volume Detail       Month Ended December 31,     In millions (unaudited)     2025     2024     % Change           Volume     ADV     Volume     ADV     Volume     ADV     Credit                                         High-grade     $ 132,950     $ 6,043     $ 124,334     $ 5,921       7   %   2   % High-yield       30,610       1,391       25,598       1,219       20       14     Emerging markets       77,319       3,515       60,240       2,869       28       23     Eurobonds       42,062       2,003       32,380       1,619       30       24     Other credit       13,067       594       13,800       657       (5 )     (10 )   Total credit trading1       296,008       13,546       256,352       12,285       15       10     Rates                                         U.S. government bonds2       426,932       19,406       393,430       18,735       9       4     Agency and other government bonds1       13,087       620       20,414       1,017       (36 )     (39 )   Total rates trading       440,019       20,026       413,844       19,752       6       1     Total trading     $ 736,027     $ 33,572     $ 670,196     $ 32,037       10       5     Number of U.S. Trading Days3             22             21                 Number of U.K. Trading Days4             21             20                                                                 Quarter Ended December 31,     In millions (unaudited)     2025     2024     % Change           Volume     ADV     Volume     ADV     Volume     ADV     Credit                                         High-grade     $ 424,563     $ 6,848     $ 400,129     $ 6,454       6   %   6   % High-yield       95,650       1,543       83,373       1,345       15       15     Emerging markets       247,140       3,986       214,439       3,459       15       15     Eurobonds       154,061       2,407       128,064       2,001       20       20     Other credit       37,086       597       38,698       624       (4 )     (4 )   Total credit trading1       958,500       15,381       864,703       13,883       11       11     Rates                                         U.S. government bonds2       1,352,808       21,819       1,608,995       25,952       (16 )     (16 )   Agency and other government bonds1       43,787       686       76,221       1,195       (43 )     (43 )   Total rates trading       1,396,595       22,505       1,685,216       27,147       (17 )     (17 )   Total trading     $ 2,355,095     $ 37,886     $ 2,549,919     $ 41,030       (8 )     (8 )   Number of U.S. Trading Days3             62             62                 Number of U.K. Trading Days4             64             64                       Year-to-Date Ended December 31,     In millions (unaudited)     2025     2024     % Change           Volume     ADV     Volume     ADV     Volume     ADV     Credit                                         High-grade     $ 1,786,664     $ 7,175     $ 1,711,275     $ 6,845       4   %   5   % High-yield       376,772       1,513       334,761       1,339       13       13     Emerging markets       979,903       3,935       859,412       3,438       14       14     Eurobonds       605,623       2,403       508,093       2,008       19       20     Other credit       153,869       617       135,975       543       13       14     Total credit trading1       3,902,831       15,643       3,549,516       14,173       10       10     Rates                                         U.S. government bonds2       6,322,098       25,390       5,511,045       22,044       15       15     Agency and other government bonds1       272,951       1,084       227,614       902       20       20     Total rates trading       6,595,049       26,474       5,738,659       22,946       15       15     Total trading     $ 10,497,880     $ 42,117     $ 9,288,175     $ 37,119       13       13     Number of U.S. Trading Days3             249             250                 Number of U.K. Trading Days4             252             253                 1 Consistent with FINRA TRACE reporting standards, both sides of trades are included in the Company's reported volumes when the Company executes trades on a matched principal basis between two counterparties. 2 Consistent with industry standards, U.S. government bond trades are single-counted. 3 The number of U.S. trading days is based on the SIFMA holiday recommendation calendar. 4 The number of U.K. trading days is based primarily on the U.K. Bank holiday schedule.

Worldline [Euronext: WLN], a European leader in payment services, today announced the commercial availability of Worldline One Commerce in the United Kingdom. This launch introduces a unified commerce solution designed to support enterprise merchants in delivering consistent and frictionless customer journeys across online, mobile, in-store, and self-service channels. Worldline One Commerce brings together Worldline’s existing payment services and operational capabilities within a consolidated back office, enabling enterprise businesses to manage transactions across all channels through a unified operational point of access. By centralising payments data and reporting, the solution improves visibility, simplifies operations and supports more efficient day-to-day management. The UK is the first market where Worldline One Commerce is commercially available. This initial deployment marks an important step in the progressive introduction of a solution.  One Commerce has been designed to operate consistently across multiple European markets, supporting enterprise merchants as they scale their activities across borders, in line with Worldline’s broader unified commerce roadmap. Built to meet the requirements of large and international merchants, Worldline One Commerce supports a wide range of omnichannel use cases, including Click & Collect, cross-channel returns, subscriptions, and unified reporting. It enables merchants to connect physical and digital channels while maintaining consistent payment performance, compliance, and operational flexibility.  Commenting on the announcement, David Gebhardt, Head of Enterprise at Worldline, said “Enterprise merchants increasingly need to manage complex payment environments while delivering seamless experiences across all channels. With Worldline One Commerce, we provide UK merchants with a unified payments foundation that simplifies operations, supports consistent customer journeys, and is built to scale across Europe.” UK enterprise merchants typically operate separate payment platforms for e-commerce and physical stores, often relying on multiple providers with limited cross-channel visibility. This fragmentation increases operational effort and slows the deployment of new customer journeys. Worldline One Commerce addresses these challenges by providing a unified point of access for payments and operations, while preserving flexibility in acquiring models. Key capabilities available with the UK launch include: Unified payment management across online and in-store channels through one back office Simplified reconciliation, reporting, and operational oversight Flexible acquiring models, combining Worldline acquiring with third-party acquirers Support for local payment methods and market preferences to optimise conversion Omnichannel customer journeys enabling faster deployment of new services The launch of Worldline One Commerce in the UK reinforces Worldline’s approach to building a unified commerce solution designed to support enterprise merchants on a pan-European scale.

The FCA has fined 2 former finance directors for their part in misleading statements being issued by Carillion plc. Richard Adam and Zafar Khan were both aware of serious financial troubles in Carillion’s UK construction business but failed to reflect this in company announcements or alert the Board and audit committee, leading to poor oversight. Mr Adam and Mr Khan have been fined £232,800 and £138,900, respectively. The fines were imposed after Mr Adam and Mr Khan withdrew their challenges to the FCA’s decision. As finance directors, the pair had responsibility for Carillion’s procedures, systems and controls relating to financial reporting. These were not sufficient to ensure that contract accounting judgments made in its UK construction business were made, recorded and reported appropriately. The FCA found both acted recklessly and were knowingly concerned in breaches by Carillion of the Market Abuse Regulation and the Listing Rules. Steve Smart, joint executive director of enforcement and market oversight at the FCA, said: 'Those in positions of responsibility have a duty to keep the market accurately and adequately informed. With Carillion, we have seen the serious impact it can have when they don’t. The action taken against Mr Adam and Mr Khan demonstrates our commitment to preventing market abuse and upholding the standards we expect.’ Background Richard Adam Final Notice (PDF). Zafar Khan Final Notice (PDF). Carillion plc (in liquidation) Decision Notice (PDF). Mr Adam was finance director of Carillion from April 2007 to 31 December 2016. He received an initial Decision Notice (PDF) dated 24 June 2022. Mr Khan was finance director of Carillion from 1 January 2017 to September 2017. He received an initial Decision Notice (PDF) dated 24 June 2022. The FCA has imposed the financial penalties on Mr Adam and Mr Khan for being knowingly concerned in breaches by Carillion of: Article 15 of MAR (prohibition of market manipulation) by disseminating information that gave false or misleading signals as to the value of its shares in circumstances where it ought to have known that the information was false or misleading; Listing Rule 1.3.3R (misleading information must not be published) by failing to take reasonable care to ensure that its announcements were not misleading, false or deceptive and did not omit anything likely to affect the import of the information; Listing Principle 1 (procedures, systems and controls) by failing to take reasonable steps to establish and maintain adequate procedures, systems and controls to enable it to comply with its obligations under the Listing Rules; and Premium Listing Principle 2 (acting with integrity) by failing to act with integrity towards its holders and potential holders of its premium listed shares. The findings in Mr Adam and Mr Khan’s Final Notices are those of the FCA and are not the subject of any judicial finding. Carillion’s former chief executive officer Mr Richard Howson received a Decision Notice (PDF) in respect of related findings, many of which are disputed by him. Mr Howson made a statutory reference to the Upper Tribunal and the hearing of his reference is scheduled to start on 16 February 2026.