Linear TV is television delivered as a continuous, scheduled sequence of programmes and commercials that every viewer of a channel receives at the same moment. The broadcaster decides what airs and when; the audience decides only whether to watch. The term covers over-the-air broadcast, cable, satellite and internet protocol television (IPTV), and exists mainly as a contrast: before digital video recorders and streaming, all television was linear. The word now marks the boundary that regulators, measurement companies and media buyers use to separate scheduled viewing from on-demand viewing, and that boundary still carries around $120 billion of global advertising a year.

How the schedule is built and sold

A linear channel runs on a programme log, a minute-by-minute plan of shows, promotions and breaks, played out from a master control room to transmitters, cable headends and satellite uplinks. Breaks are divided into slots, conventionally 30 seconds long, though 15-second and 60-second units are common. Each commercial carries an identifier, originally an Industry Standard Coding Identification (ISCI) code and, in the United States since 2003, an Ad-ID, so that it can be scheduled, verified and billed.

Ownership of the slots is split. A national network sells most of the time in each break, while affiliated local stations and pay-TV distributors keep a portion. Time Warner Cable described its share in its 2006 annual report as "generally two minutes per hour" of licensed cable programming, time known as local avails. In digital systems the network embeds cue messages defined by SCTE-35, a Society of Cable Telecommunications Engineers standard, in the feed. When a cue reaches a headend, a splicer replaces the national placeholder with a locally sold spot. Addressable systems push the same decision down to the set-top box, so two households watching one programme can see different commercials.

Prices follow audiences, not served impressions. American buyers and sellers negotiate against Nielsen commercial ratings, principally C3: the average audience of a programme's commercial minutes, live plus three days of recorded playback. A gross rating point (GRP) equals one per cent of the target population, and cost per point or cost per thousand (CPM) converts that into money. Most network inventory is committed in the spring upfront, where buyers lock rates months ahead and sellers guarantee delivery, supplying extra spots if ratings fall short. The remainder sells in the scatter market closer to air. Britain works differently: linear time trades in impacts, one viewer watching one commercial, measured by the Barb panel and priced against station averages.

Ad load is capped by law in Europe but largely not in the United States. The Audiovisual Media Services Directive (AVMSD) limits advertising and teleshopping to 20 per cent of two windows, 06:00 to 18:00 and 18:00 to midnight, which works out at 144 and 72 minutes respectively. American federal limits apply only to children's programming: 12 minutes an hour on weekdays and 10.5 at weekends under the Children's Television Act of 1990. Wurl, a company that distributes streaming channels, put typical linear load at around 15 minutes an hour in March 2025, against roughly nine on connected TV.

From the only television to a retronym

Commercial television began in the United States on July 1, 1941, when WNBT in New York aired a Bulova watch announcement before a Brooklyn Dodgers game. The company paid $9 in air and station charges, by the most widely cited account. Britain's first commercial ran on ITV on September 22, 1955. For half a century afterwards, schedule-bound viewing was simply television.

Time-shifting broke that assumption. TiVo shipped the first consumer digital video recorder on March 31, 1999, making it trivial to skip breaks. Nielsen answered with commercial-minute ratings, first released on May 31, 2007, which counted recorded playback only for the commercial minutes viewed within three days.

Europe gave the word legal weight. A European Commission proposal in 2005 to overhaul the 1989 Television without Frontiers Directive split audiovisual services into linear and non-linear categories. Directive 2007/65/EC adopted the split on December 11, 2007, and the codified AVMSD of March 10, 2010 still defines a linear service as one provided "for simultaneous viewing of programmes on the basis of a programme schedule". The test is the schedule, not the network: a scheduled internet channel is linear, a broadcaster's catch-up player is not. Directive (EU) 2018/1808, adopted on November 14, 2018, replaced the earlier ceiling of 20 per cent per clock hour, 12 minutes, with the daily windows.

Automation came late. Google opened linear buying inside Display & Video 360, announcing on May 14, 2019 that US network affiliates were reachable through a beta integration with WideOrbit. Measurement moved in parallel: Nielsen replaced panel-only ratings with Big Data + Panel on September 2, 2025, merging a 42,000-home panel with device data from about 45 million households.

Why it matters to advertisers

Linear still collects most television money, even where it no longer collects most viewing. Global linear advertising reached $123.5 billion in 2025, down 3.8 per cent, and will fall to $120.3 billion in 2026, out of total television revenue of $167.4 billion, according to WPP Media's December 2025 forecast.

Viewing moved faster. Nielsen's The Gauge recorded streaming overtaking broadcast and cable combined for the first time in May 2025, by 44.8 per cent to 44.2 per cent. By July 2026, the latest edition as of September 2026, streaming held 49.0 per cent of US television time against 19.5 per cent for broadcast and 18.7 per cent for cable. Among adults aged 18 to 49, Nielsen's 2026 planning guide found streaming accounted for 66.7 per cent of ad-supported viewing.

Why has spending lagged? Live sport and news keep large simultaneous audiences on linear, and inventory is plentiful and cheap. A vendor study by iSpot covering 224.2 billion impressions from 87 brands found linear taking 67.5 per cent of TV ad spend at an average frequency of 26.5 exposures, against 7.3 on connected TV; EMARKETER data in the same analysis put linear at 86.9 per cent of TV ad impressions but 54.2 per cent of viewing time. In Britain, linear sells at four to five dollars per thousand impressions, against 22 to 25 dollars for broadcaster streaming, according to Guideline data cited in a report Liberty Sky Advisors prepared for the transmitter operator Arqiva.

Habits differ by market. The RTL AdAlliance Living Room Study found 64 per cent of Europeans watch television daily and 53 per cent often watch local content on linear channels.

Where the category is contested

Measurement is the first fault line. The Media Rating Council suspended accreditation of Nielsen's national and local television services on September 1, 2021 over undercounting. In March 2026 the Video Advertising Bureau accused Nielsen of withholding a February Gauge that showed linear at 47.4 per cent and streaming at 41.9 per cent under a revised methodology, reversing January's order. Greg Peters, Netflix co-chief executive, replied on April 16: "It changes Nielsen's numbers, not actual viewing behaviours."

Forecasts diverge sharply. The IAB expects US linear spending to fall 1.5 per cent in 2026, based on a survey of buyers. MoffettNathanson projects US core linear revenue falling 6 per cent to $51.6 billion, according to MediaPost. One tracks buyer intentions, the other seller revenue, and the two cannot be reconciled directly.

Definitions shift the totals. Since February 2023, Nielsen has credited live channels watched through virtual distributors such as YouTube TV to broadcast and cable rather than streaming, so linear in The Gauge already includes internet-delivered viewing. Joshua Chasin of the measurement consultancy KnotSimpler put the problem in a December 2025 comment on MediaPost: "linear is a mode of consumption; streaming is a mode of distribution."

Trading friction is the last complaint. Schedules are fixed weeks ahead, and local inventory in particular has stayed slow and manual to buy.

Not the same as

Linear ad. In the IAB Video Ad Serving Template (VAST), a linear ad is any spot that interrupts content, the digital equivalent of a break, as opposed to non-linear overlays. A pre-roll on an on-demand service is a linear ad on non-linear television.

Connected TV. CTV names a device, an internet-connected screen. Linear channels reach it through apps and virtual distributors, so the two overlap.

FAST. Free ad-supported streaming television runs scheduled channels over the internet. Under the European test, which turns on the schedule, it can qualify as linear, yet Nielsen counts it as streaming.

Addressable TV. Household-level targeting inside linear feeds through set-top boxes. It is a capability of linear delivery rather than an alternative to it.

Recent developments

Programmatic access is widening. Comcast Advertising made linear inventory biddable through private marketplaces on October 23, 2025, running on FreeWheel's Buyer Cloud. AMC Global Media took its linear supply programmatic through Magnite in April 2026. On September 10, 2026, Magnite and ITN placed ITN's seller agent inside Magnite's orchestration layer for local linear buying, with full integration due in the fourth quarter; ITN's network spans 75 broadcast ownership groups and more than 1,100 stations.

European revenue keeps shrinking. RTL Group estimated the German net linear advertising market fell 6 to 7 per cent in the first half of 2026, and the French market 9 to 10 per cent. Britain is choosing between switching off digital terrestrial television in 2034 or 2044, and the Arqiva-commissioned assessment estimates the earlier date would leave commercial public service broadcaster advertising 16 per cent lower in 2034. In the United States, Nielsen's seven currency changes took effect on August 31, 2026, with revisions to The Gauge due this autumn.

Timeline

  • July 1, 1941: WNBT in New York airs a Bulova announcement, the first licensed US television commercial
  • September 22, 1955: ITV broadcasts Britain's first television commercial
  • October 3, 1989: The Television without Frontiers Directive is adopted
  • 1990: The Children's Television Act caps advertising in US children's programming
  • March 31, 1999: TiVo ships the first consumer digital video recorder
  • 2003: Ad-ID replaces ISCI codes for identifying US commercials
  • 2005: The European Commission proposes splitting audiovisual services into linear and non-linear
  • May 31, 2007: Nielsen commercial ratings become available
  • December 11, 2007: Directive 2007/65/EC writes the linear and non-linear distinction into EU law
  • March 10, 2010: The Audiovisual Media Services Directive is codified as Directive 2010/13/EU
  • November 14, 2018: Directive (EU) 2018/1808 replaces the hourly advertising cap with daily windows
  • May 14, 2019: Google announces linear TV buying in Display & Video 360
  • May 2021: Nielsen publishes the first edition of The Gauge
  • September 1, 2021: The Media Rating Council suspends Nielsen's national and local accreditation
  • February 2023: Nielsen credits linear viewing through virtual distributors to broadcast and cable
  • May 2025: Streaming passes broadcast and cable combined in The Gauge; ITN and Magnite launch programmatic local linear buying
  • September 2, 2025: Nielsen launches Big Data + Panel as US currency
  • October 23, 2025: Comcast Advertising makes linear inventory biddable through private marketplaces
  • March 26, 2026: The Video Advertising Bureau accuses Nielsen of suppressing February Gauge data
  • April 2026: AMC Global Media brings linear inventory into programmatic buying through Magnite
  • August 31, 2026: Nielsen's seven currency changes take effect
  • September 10, 2026: The IAB revises its 2026 linear forecast to minus 1.5 per cent; Magnite and ITN announce agentic local linear buying

Summary

Who. Broadcast networks, local stations, cable channel groups and pay-TV distributors sell linear inventory. Agencies and advertisers buy it, increasingly through platforms such as FreeWheel, Magnite and Display & Video 360. Nielsen in the United States and Barb in Britain supply the currencies, the Media Rating Council accredits them, and the European Union and national regulators set advertising limits.

What. Television delivered on a fixed schedule to every viewer of a channel at once, by broadcast, cable, satellite or IPTV, and sold in commercial slots priced on ratings, impacts or CPMs. Advertising loads run around 15 minutes an hour in the United States, by one vendor's estimate, and are capped at 20 per cent of daily windows in the European Union.

When. Commercial linear television dates from July 1, 1941. The word became necessary after the digital video recorder arrived in 1999, and entered EU law in December 2007. Streaming first overtook it in US viewing share in May 2025.

Where. Everywhere television is broadcast, with the heaviest reliance in Europe, where 64 per cent of people watch daily, and the fastest erosion in the United States, where linear held under 40 per cent of television time in July 2026.

Why. A shared schedule assembles large simultaneous audiences, which matters most for live sport, news and launches. That reach, cheap inventory and entrenched trading conventions keep roughly $120 billion a year in linear, even as viewing drifts to on-demand services and buyers push the medium onto programmatic rails.