London vs Manchester measurement practices, agency structures and consent tooling

What to take away

Two agency markets: London scale versus Manchester in-house depth

London agency types cluster into four groups. Network media agencies such as EssenceMediacom and Havas buy media and measurement together. Independent performance agencies such as Brainlabs and Jellyfish sell paid search and paid social with reporting attached. Specialist measurement consultancies sell incrementality testing and media-mix modelling as a standalone service.

Adtech and analytics vendors sit alongside them, selling tooling that agencies resell.

That structure exists because London holds the densest concentration of UK marketers, alongside the ICO, the CMA and most large adtech firms. A brand buying in London is usually buying access to people it cannot hire quickly, not buying a process it could run itself.

Manchester in-house team types look different. Ecommerce and retail brands such as THG, Boohoo and AO.com run their own analytics function. Media and publishing businesses run audience measurement internally. Fast-growing digital brands hire a small measurement lead and one or two analysts. Agencies such as Havas Manchester and McCann Manchester tend to support that team rather than replace it.

Manchester sits in North West England, and its media and ecommerce base has grown without the capital's agency density. That matters commercially: an in-house team in Manchester often pays less for the same analyst skill. The Manchester team also keeps the resulting data.

Typical Manchester in-house analyst salaries are £35,000 to £55,000, while London agency measurement specialists are typically quoted at £600 to £1,200 a day.

London and Manchester have built different supplier markets. London sells measurement specialists by the day; Manchester sells channel execution to a team that already measures itself. For a buyer comparing quotes, that is the first thing to establish.

Consent management tooling each market actually deploys

Consent platforms UK buyers choose fall into three bands. Enterprise platforms such as OneTrust, TrustArc, Didomi and Sourcepoint handle multi-domain estates, regional rule sets and audit trails. Mid-market platforms such as Cookiebot, Osano and CookieYes cover a single site with tag control and a preference centre. Lightweight banners, including free WordPress plugins, cover basic opt-in and little else.

London agencies overwhelmingly deploy enterprise platforms such as OneTrust or TrustArc. They need one consent layer across many client domains, plus evidence they can hand to a client's legal team. Agency measurement teams also want consent signals flowing into their analytics and media platforms, not sitting in a separate dashboard.

The ICO guidance on storage and access technologies is the document behind most of these builds, because it covers cookies, pixels, local storage and device fingerprinting in one place. Consent tooling that only handles cookies is now visibly incomplete.

The ICO wrote to the UK's most visited websites in 2023 and gave them 30 days to make changes. It published its position on consent or pay models in 2024.

Manchester in-house teams more often run mid-market platforms such as Cookiebot or Osano. A single brand domain, a preference centre, and a direct integration into the analytics warehouse. They tend to configure consent themselves rather than buying a managed service.

The IAB UK Gold Standard letter matters here because it sets consent expectations that agencies and publishers sign up to. London agencies are more likely to be asked to evidence compliance against it during procurement. Manchester teams meet it more often through publisher and adtech contracts than through their own agency.

London and Manchester also split on who turns the dials. London agencies run consent as a managed service across client estates; Manchester in-house teams configure it themselves and pass consent states straight into their warehouse.

For a worked example, take a retailer with one transactional site and a content site. A London agency would put both behind one enterprise consent platform such as OneTrust, map consent states into media buying, and report on consent rate as a media metric.

A Manchester in-house team would put the shop behind a mid-market platform such as Cookiebot, pass consent state into the warehouse, and report on consented revenue rather than consented traffic.

First-party data ownership and who holds the client relationship

First-party data ownership follows the contract, not the tooling. In London, the agency usually holds the analytics and media accounts, the data processing agreement, and the client relationship. The brand owns the data in law but depends on the agency to reach it.

That arrangement is efficient and fragile. When the relationship ends, exporting clean, consented, joined-up data takes weeks. Buyers should agree the export format before the contract starts, not after.

Manchester in-house teams invert this. The brand holds the analytics account, the warehouse and the customer record. Agencies get access, not ownership. That makes switching suppliers cheaper and makes the measurement lead the most exposed person in the team.

A sound first-party data strategy starts with deciding which side of that line you want to be on before you brief anyone. The choice determines your hiring plan as much as your tooling.

There is a middle path. Some brands keep the warehouse and identity resolution in house, then buy channel execution and incrementality testing from agencies. That works well when the in-house team has at least one person who can own data quality.

Whichever path you take, the data processing agreement should name what happens to consented identifiers at the end of the contract. That single clause causes more disputes than any measurement methodology.

Attribution approaches compared across the two cities

Attribution comparison between the two markets comes down to what each side trusts. London agencies lean on platform-reported attribution tools such as Google Ads, Meta Ads Manager and Adobe Analytics, media-mix modelling, and incrementality tests run by specialist teams.

Manchester in-house teams lean on server-side tracking, warehouse joins and clean rooms such as Google Ads Data Hub, InfoSum or Snowflake Data Clean Room.

Platform-reported attribution is fast and biased toward the platform reporting it. Media-mix modelling covers channels that cannot be tracked and needs enough historical spend to be stable. Incrementality testing, usually geo holdouts or audience splits, is the closest thing to a neutral answer and the slowest to run.

In London, the agency structure supports all three because specialists sit in one building or one group. The IPA guidance on media practice covers agency-side measurement, which is useful when a client wants to benchmark a proposed approach.

Manchester teams more often start from the warehouse. Events land server-side, identity is resolved in house, and channel contribution is modelled from joined data. That approach is cheaper at scale and harder to set up, because it needs engineering time the brand has to fund.

The two markets also differ in reporting cadence. London agencies typically report monthly with a quarterly deeper read. Manchester in-house teams often report weekly to the commercial team and monthly to the board, because the analyst sits close to trading.

If you are comparing suppliers, a structured supplier comparison by service model will tell you more than a comparison by tool. Tool lists converge; service models do not.

What buyers should ask each type of supplier

Ask London agencies these questions before signing.

Ask Manchester in-house teams and their supporting agencies these questions.

Use this checklist when scoring answers.

Public evidence helps here. Reading agency reviews before shortlisting saves time, and bringing in independent measurement consultants for a scoring exercise is cheaper than renegotiating a bad contract later.

The IPA measurement evidence covers UK advertising measurement, useful when you need to judge whether a proposed method is standard or bespoke. The IAB UK Gold Standard letter is the reference to cite when a supplier's consent position looks loose.

Common questions