City view · 803 companies

Marketing agencies in London

803 UK marketing agencies name London on their website and publish an email address, as of September 29, 2026. W1 is the busiest postcode district among those that publish one, and WordPress runs on 56% of their websites.

Search marketing agencies in London in Warmerly Open this search

Searching is free. You only spend allowance when you export.

Postcode districts

Which parts of London they cluster in

242 of the 803 publish a postcode. Among them, W1 leads with 35. Districts with fewer than five companies are left out.

London marketing agencies by postcode district (companies)
W1	35 (14%)
WC2	27 (11%)
EC1	19 (8%)
EC2	17 (7%)
E1	14 (6%)
N1	10 (4%)
SE1	7 (3%)
WC1	5 (2%)
N5	5 (2%)
EC3	5 (2%)

Contact routes

How marketing agencies in London can be reached

Every company here publishes an email address. These are the other routes and signals their websites carry.

Company LinkedIn page66% · 532

Contact form28% · 224

A second route for when email goes unanswered.

Phone number24% · 195

Hiring or links a careers page14% · 111

Growing firms buy more. A useful first filter.

Companies House number15% · 122

VAT number5% · 41

Email and websites

What marketing agencies in London run on

Who hosts their email decides which spam filter reads your message. What their site is built on says what else they already pay for.

Email provider

Email providers of marketing agencies in London
Google Workspace	344 (43%)
Microsoft 365	134 (17%)
Self-hosted	68 (8%)
Hostinger	25 (3%)
Other or unknown	232 (29%)

Read from each domain's public MX record. If most of your list is on one provider, warm up a mailbox on that provider first. Filter by provider in the lead finder.

Built with

WordPress 56%
Contact Form 7 20%
Elementor 18%
WooCommerce 8%
Meta Pixel 7%
Squarespace 6%
Next.js 6%
HubSpot 5%

Share of these companies whose homepage loads each technology. Google Analytics is left out because nearly everyone runs it.

Founding year

How established marketing agencies in London are

142 of them (18%) state a founding year on their site. This is how those split.

Marketing agencies in London by founding year
Before 1980	3 (2%)
1980 to 1999	15 (11%)
2000 to 2009	35 (25%)
2010 to 2014	35 (25%)
2015 to 2019	38 (27%)
2020 or later	16 (11%)

Outreach playbook

How to reach marketing agencies in London

What we have learned about emailing marketing agencies. The numbers above tell you how many there are; this is how to get a reply.

Agencies are pitched constantly and spot a template in one line. What works is something they can resell or that makes a client retainer easier to defend: a white-label deliverable, a faster report, a new service line they can price.

Who to email

Founder or managing director at agencies under 20 people. They still sign every supplier.
Head of operations or delivery lead at larger shops, who owns the tooling budget.
New business or growth director if you are offering them clients, not software.

What they will say back

“We already have a tool for that.”: Ask what it costs per client seat. Agencies feel per-seat pricing more than anyone, and a flat price is often the real opening.
“Send me something to look at.”: Send a one-page example built on one of their own client niches, not a deck. It proves you looked.
“Not a priority this quarter.”: Ask when their next client onboarding wave is. Agencies buy right before they need to deliver more.

A first email that fits a London firm

Subject: a resellable add-on for your retainers

Hi [first name], noticed [agency] runs paid social for a lot of local service brands. Most agencies we talk to lose margin on reporting. We built a way to turn that into a line item clients pay for. Worth a 10 minute look?

Replace the bracketed parts per company. In a Warmerly campaign they fill from the lead's own fields.

When to send

Tuesday to Thursday mornings. Monday is client status calls and Friday afternoon is reporting, so both bury cold email.

Questions

Marketing agencies in London: common questions

How many marketing agencies are there in London?

803 UK marketing agencies in Warmerly's database name London on their website and publish an email address, counted on September 29, 2026. A company is matched when its site text mentions London, the same way a city search works in the lead finder, so a firm based elsewhere with a London office is included.

Which email provider do most marketing agencies in London use?

Google Workspace runs email for 43% of them, followed by Microsoft 365 at 17%. It is read from each domain's public MX records. It matters for cold email because Google and Microsoft filter differently, so a sending mailbox on the same provider as most of your list is worth warming up first.

How is London matched?

By full-text search over each company's own website text, the same match the lead finder uses when you type London into the city filter. It is broader than a registered address: 242 of these companies publish a postcode, which is where the district breakdown on this page comes from.

Can I get a list of marketing agencies in London?

Yes. Searching the database in Warmerly is free, and you see the same count as this page before spending anything. Exporting or adding companies to a campaign uses your plan's monthly lead allowance. Every result is a business contact route the company publishes itself, and any company that has asked to be removed is excluded. This page shows totals only, never individual companies.

More marketing agencies

Other industries in London

Where the numbers come from

Search 803 marketing agencies in London

Filter them by size, founding year, technology and hiring, see what each record holds, then send from warmed-up mailboxes in the same tool.

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