What is programmatic advertising?

Programmatic advertising is the automated purchase of individual advertising impressions. You set an audience, a budget and the rules you want enforced; software then decides, impression by impression, whether to bid and what to pay, and an auction settles it in roughly the time a page takes to start loading. The word describes the transaction rather than the medium, which is why a streaming TV advert, a podcast pre-roll, a roadside screen and a display banner can all be programmatic buys and still have almost nothing else in common.

Four parties are usually in the path and three of them take a share. A demand-side platform bids on the buyer's behalf. A supply-side platform sells the publisher's inventory and sets the floor price it will accept. An ad exchange runs the auction between the two. The publisher gets what is left, and the gap between what an advertiser pays and what a publisher receives is why working media (the share of your budget that actually buys advertising) is the number worth asking any platform for, ahead of its headline rate.

Across the UK market, the channels that genuinely transact this way are CTV and streaming, digital audio and podcasts, digital out-of-home and display. Paid search and paid social are auctions as well, but they run inside Google's and Meta's own systems against inventory those companies control, so the industry rarely files them under programmatic even though the buying rhythm feels the same. Premium audio and named-show podcast inventory sit in between: the deal is negotiated first and then executed programmatically against a deal identifier.

Cinema and addressable television do not transact this way in the UK at all. Both are a booking brief, a clearance step and an insertion order, with lead times measured in days rather than milliseconds, so a proposal that lists them as programmatic inventory is describing paperwork somebody is doing by hand. Both sit outside an AdBuyMCP awareness plan. The supply page grades every connector AdBuyMCP registers, so you can see which ones are APIs and which ones are workflows.

AdBuyMCP sits above the programmatic layer rather than inside it. You confirm your market and how often it should see you, 3, 5 or 12 times a week; AdBuyMCP balances the budget across out-of-home, streaming TV, podcasts and ChatGPT ads and buys through the sellers, at one all-in monthly price.

A programmatic advertising agency buys programmatic media on an advertiser's behalf. It holds or accesses the demand-side platform seat, plans the audience and the budget, traffics the creative, watches pacing and supply paths daily, and reports what happened. What you are paying for is the trading desk and the person sitting at it. A buying interface assumes somebody who understands bid strategies, inventory quality and pacing and who will look at it daily, and a seat nobody looks at spends the budget anyway.

UK fees are a retainer, a share of the media or both, with the media paid on top. On desk research checked 20 October 2026, UK agencies charge 10% to 30% of monthly ad spend, and retainers run at £1,250 to £3,500 a month for one channel and £3,500 to £16,750 a month for several. The ranges are wide because the market is: the rate moves with your volume, your channel mix and how much of the work stays with you.

Two questions separate one agency from another and neither of them is the rate. The first is the working-media percentage: how much of each pound reaches a publisher once the platform, the exchange, the supply-side platform and the data have taken their shares. The second is whether any of the media is bought as principal and resold to you at a margin (legal, common, and invisible unless you ask). An agency that answers both plainly has told you something about how it is run.

An agency is the right answer when you need judgement more than tooling: no in-house media capability, a creative problem as much as a buying one, or a procurement process that wants references, an insurance profile and somebody accountable on the phone. If you need an account team on the phone, the agency is the better buy, and the comparison page sets the two side by side and says where the agency is ahead.

What AdBuyMCP offers instead is a price you can see before you talk to anyone. You choose how often your market should see you, AdBuyMCP balances the budget across the four channels, and you approve the plan and every ad before anything runs. The monthly price is all-in, covering the media and AdBuyMCP's margin, where an agency's retainer usually comes on top of the media.