Subway advertising: who sells it, what the formats are, and how the audience is counted

Subway advertising is bought from the system's advertising concessionaire, not from the transit authority. OUTFRONT Media holds New York, Washington and BART; Intersection holds Chicago, Philadelphia, Atlanta and SFMTA. Formats are specified in inches for static units and in pixels and loop seconds for digital ones.

Subway advertising sits inside the broader transit category, but it plans differently from anything else in it. The inventory is fixed in place while the audience moves through it, the specifications are published to the inch and the pixel, and the rules on what may be said are set by a public authority rather than by a media owner. Three things decide whether a plan survives contact with the system: who you are actually buying from, what the unit physically is, and what the authority will refuse to run.

Who actually sells subway advertising?

Almost never the transit authority. Systems award a concession, usually a decade or more and usually with a guaranteed minimum payment to the authority, and the concessionaire sells and installs the media. That is why two systems in the same city can have two different sales contacts, and why a national buy touches several vendors.

San Francisco is the clearest illustration. BART is sold by OUTFRONT Media; Muni buses, light rail and the cable cars are sold by Intersection. A brief that says "San Francisco transit" is two buys, two sets of specifications and two contracts. Boston and Los Angeles split the same way: Boston by asset type, Los Angeles between rail and bus.

What are the standard static subway ad sizes?

Static transit units are standardised across systems more than any other out-of-home format. The names travel with the sizes, which is why a creative team can build once for a multi-market transit buy in a way that is impossible for billboards.

Individual systems publish their own production sizes that differ slightly from the national kit. Los Angeles Metro, for instance, publishes rail poster sizes of 21" × 22.25" for light rail and 21" × 22.375" for heavy rail, and a King with a 27" × 141" live area inside the 30" × 144" trim. Always build to the specification sheet for the system you bought, not to the category name.

How are digital subway units specified?

Digital transit is bought as a share of a loop rather than as a site. Two numbers decide how much of the audience is yours: the spot length and the loop length. A network with an eight-second spot in a 64-second loop gives one advertiser one-eighth of every cycle.

Note what is missing from every one of those rows: audio. Transit digital is silent by specification, not by convention. Creative that needs a voiceover to make sense does not belong in a station.

Station dominations, which take an entire station with a combination of static, digital and direct-application media, are quoted custom. There is no published dimension because the unit is the station.

What will each system refuse to run?

Content standards are the part of a transit plan most likely to kill finished creative, and they are not consistent between authorities. The same advertisement can be accepted in one city and rejected in the next, and the legal footing underneath those decisions is itself different from system to system.

The forum designation is not a technicality. The MTA calls its advertising space a nonpublic forum, which gives it wide latitude to exclude categories of speech; SFMTA calls its space a limited public forum, which is a narrower position. In Washington, the restriction on issue advertising was preliminarily enjoined in 2024 for lacking workable standards. Any plan that assumes one national rule on what can be said in transit is wrong in at least one of its markets.

Why is ridership not an impression count?

This is where transit plans most often overstate themselves. Ridership counts journeys. An impression count estimates how many people were likely to notice a specific advertisement. Geopath, the industry's audience measurement body, keeps the two apart by definition: circulation measures traffic volume and estimates only the number of people with an opportunity to see a display, while impressions are the number likely to notice the advertisement. A visibility adjustment converts the first into the second, which means an impression figure is always a fraction of the circulation figure it came from.

Two practical consequences. First, a vendor deck quoting system ridership as "impressions" has skipped the adjustment. Second, the denominators themselves are worth checking: OUTFRONT's MTA marketing page cites 2.6 billion rides a year, while the MTA's own published totals for calendar 2025 are about 1.28 billion subway rides plus roughly 442 million across all MTA bus operations, of which New York City Transit buses carried 352,146,093. Ask which number a proposal is built on.

Transit stations only entered the current generation of measured out-of-home inventory with the 2023 forecast, which is recent enough that measurement coverage varies by system. How that measurement works, and why moving surfaces are harder than fixed ones, is covered in full on how out-of-home impressions are measured.

How big is each system, in its own published numbers?

These are published ridership figures, not audience estimates, and they cover different periods: authorities report on calendar years, fiscal years and months, and they are not directly comparable to each other.

For context on the category as a whole: transit was the fastest-growing out-of-home segment in the United States in 2025 for the second consecutive year, up 9.2%, against 3.6% growth for out-of-home overall on record revenue of $9.46 billion.

New York, specifically

New York is both the largest transit advertising market in the country and the one with the most format variety: car cards, platform posters, turnstiles, in-car and station digital, brand trains and full exterior wraps, all under one concession. It also has a second vehicle-side market alongside the subway, in taxis and for-hire vehicles, that answers to an entirely different regulator. Both are covered in depth at Advertise in NY, which is where the format-by-format New York comparison lives; this page stays national.

How do you reach the same riders at street level?

Every subway rider is a pedestrian at both ends of the trip, and the concession stops at the station door. The formats that carry on from there are on cars: Firefly sells digital and static tops on taxis and rideshare vehicles, routed by neighbourhood and daypart, and 360, 270 and 180 wraps, and names 15 markets for the tops; Carvertise sells wraps on rideshare drivers' cars; Can't Miss US runs LED trucks where the city allows them. A station domination and a fleet of tops around the same station are two contracts under two regulators, the transit authority and the city's for-hire licensing body, and the second is covered on transit advertising.

What should you establish before creative is produced?

• Which vendor holds the concession for the exact part of the system you want, and whether the city splits it.
• The unit's trim size and its live area. They are not the same, and the difference has eaten copy before.
• For digital: pixel dimensions, spot length, loop length, and whether the creative may move.
• Whether audio exists on the network. In transit, assume it does not.
• Whether the audience figure in the proposal is Geopath-measured or a vendor estimate, and which one the contract guarantees.
• The system's content standards, read in full, before the creative is signed off rather than after.
• Whether production and installation sit inside the quoted price or outside it.

Sitting above all of it, the category question of which format earns the budget in the first place is covered on out-of-home advertising, and the vendor map, who owns what and who to call, on outdoor advertising companies.