{"page":"/blog/ad-tech-tax-explained","modified":"2026-10-18","license":"https://creativecommons.org/licenses/by/4.0/","columns":["Study (publisher, date)","Data","Intermediaries' share or publisher share","Working media (quality)","Scope notes"],"rows":[["ANA, \"Programmatic: Seeing through the financial fog\" (2017), as summarised by the CMA","6.6 billion impressions, $36.4 billion, 445 campaigns, 7 advertisers, 2017","Buy-side charges 28% of spend, including about 9% data (CMA, Appendix R, 1 July 2020)","Not measured","DSP data only; no sell-side fees"],["Plum Consulting for DCMS (January 2019)","Expert estimates","Publishers receive 62p of every £1 (CMA, Appendix R, 1 July 2020)","Not measured","Indicative, not transactional"],["eMarketer (August 2019)","US forecast model","Nearly one third of US non-social programmatic display spend to intermediaries; fees of $11.6 billion in 2019, forecast $13.4 billion in 2020 and $15.3 billion in 2021 (eMarketer, August 2019; AdExchanger, 5 August 2019)","Not measured","Forecast; excludes agency fees"],["ISBA and PwC, study I (May 2020)","15 advertisers, 12 agencies, 5 DSPs, 6 SSPs, 12 publishers; 267 million impressions, 31 million matched, Q1 2020, UK","Publishers 51%; unknown delta 15% (ISBA, May 2020)","Not measured","Includes agency fees; premium participants, \"likely a best case\""],["UK CMA (1 July 2020)","2019 aggregated fee data from major UK intermediaries","Publishers about 65%; adtech take about 35% (CMA, Appendix R, 1 July 2020)","Not measured","Excludes agency, third-party data and verification fees not charged via the DSP"],["Adalytics (April 2022)","Log-level data from DSPs, SSPs, exchanges and publishers, US","DSP plus SSP up to 35% on average of a $10 bid; 22% to 45% for half of impressions; SSP median about 20% (Adalytics, April 2022)","Not measured","Excludes CTV and direct-sold; no agency fees"],["ISBA and PwC, study II (18 January 2023)","Same design, 2022 data, UK","Unknown delta 3%; match rate 58% (from 12%); publisher share up 8% (ISBA, 18 January 2023)","Not measured","Participants had adopted the ISBA toolkit; \"should not be taken as representative\""],["ANA, Programmatic Media Supply Chain Transparency Study (June and December 2023)","21 advertisers, $123 million, 35.5 billion impressions, September 2022 to January 2023, US","Transaction costs 29%; seller revenue 71% (ANA, December 2023)","36 cents; $22 billion of a $88 billion market wasted (ANA, December 2023)","Web and mobile only; excludes agency, ad serving, managed service fees"],["ANA Benchmark, Q4 2024 (12 December 2024)","37 participating, 21 contributing; 38.5 billion impressions; $235 million; April to September 2024 (ANA Benchmark, Q1 2025)","Transaction costs 29.8% (ANA Benchmark, Q1 2025)","43.9% (ANA, 12 December 2024)","First benchmark release; CTV partly included"],["ANA Benchmark, Q1 2025","39 participating, 23 contributing; 41.9 billion impressions; $242 million; November 2024 to March 2025","Transaction costs 26.1% (ANA Benchmark, Q1 2025)","41.0% (ANA Benchmark, Q1 2025)","CTV fully included at 30.4% of spend, which raised non-measurable and non-viewable shares"],["ANA Benchmark, Q2 2025","39 participating, 21 contributing; 18.6 billion impressions; $146 million; April to June 2025 (ANA Benchmark, Q3 2025)","Transaction costs 25.2% (ANA Benchmark, Q3 2025)","37.0%; waste estimated at $26.8 billion (ANA Benchmark, Q3 2025; Measured, 15 August 2025)","CTV 44.2% of spend"],["ANA Benchmark, Q3 2025 (5 November 2025)","39 participating, 21 contributing; 17.5 billion impressions; $142 million; July to September 2025","Transaction costs 23.8%; seller revenue 76.2% (ANA Benchmark, Q3 2025)","39.0% all environments; 47.1% web and mobile (ANA, 5 November 2025)","CTV 45.6%; PMP 81.6%; $13.6 billion recovered since 2023"],["ANA Benchmark, Q1 2026 (27 May 2026)","86 participating, 66 active","Cohorts differed by 2.4 points on transaction costs (ANA, 27 May 2026)","43.3%; top cohort 54.0%, bottom 32.1% (ANA, 27 May 2026)","Participant base more than doubled"],["ANA Benchmark, Q2 2026 (6 August 2026)","n/d","Transaction costs 27.2% (ANA via Fiducia, 6 August 2026)","45.1%; top cohort 52.3%, bottom 31.1% (ANA via Fiducia, 6 August 2026)","CTV 41.6%; non-viewable 10.1%; IVT 0.1%"]],"sourceUrls":[["https://assets.publishing.service.gov.uk/media/5fe49625e90e071207e10eff/Appendix_R_-_fees_in_the_adtech_stack_WEB.pdf"],["https://assets.publishing.service.gov.uk/media/5fe49625e90e071207e10eff/Appendix_R_-_fees_in_the_adtech_stack_WEB.pdf"],["https://www.emarketer.com/content/emarketer-s-new-ad-tech-tax-estimates-show-one-third-of-spending-goes-to-intermediaries","https://www.adexchanger.com/analysts/emarketer-ad-tech-gets-a-tax-cut-as-programmatic-fees-decline/"],["https://www.isba.org.uk/system/files/media/documents/2020-12/executive-summary-programmatic-supply-chain-transparency-study.pdf"],["https://assets.publishing.service.gov.uk/media/5fe49625e90e071207e10eff/Appendix_R_-_fees_in_the_adtech_stack_WEB.pdf"],["https://adalytics.io/blog/adtech-supply-fees"],["https://www.isba.org.uk/knowledge/second-programmatic-supply-chain-transparency-study"],["https://www.adslot.com/wp-content/uploads/2023/12/ana-programmatic-media-supply-chain-transparency-study.pdf"],["https://s3.amazonaws.com/media.mediapost.com/uploads/ANAQ12025Programmatic.pdf","https://www.ana.net/content/show/id/pr-2024-12-programmatic"],["https://s3.amazonaws.com/media.mediapost.com/uploads/ANAQ12025Programmatic.pdf"],["https://s3.amazonaws.com/media.mediapost.com/uploads/Q32025ProgrammaticTransparencyBenchmark.pdf","https://www.measured.com/blog/ana-finds-26-8b-in-programmatic-waste-what-marketers-can-do-now/"],["https://s3.amazonaws.com/media.mediapost.com/uploads/Q32025ProgrammaticTransparencyBenchmark.pdf","https://www.ana.net/content/show/id/pr-2025-11-transparency"],["https://www.ana.net/content/show/id/pr-2026-05-programmatic"],["https://www.fiducia.eco/post/ana-programmatic-transparency-benchmark-q2-2026-working-media-efficiency-reaches-a-record-45"]]}