Disclosure: we are Fortitude Media and Online Marketing is our department. We have also spent twenty years hiring agencies, being pitched by agencies and, in a former life, being one. The cases where an agency is the right buy are below, in plain sight.
Last checked: 20 July 2026.
The short answer
A mid-market digital agency retainer runs £2,000 to £10,000 a month and buys you a team's attention in monthly cycles: strategy, campaigns, meetings, and a report. Fortitude's Online Marketing department costs £229 a week, about £992 a month, and buys you specialists for ads, SEO, email and content working your channels every day: budgets rebalanced, keywords and copy tested, emails shipped, underperformance caught the day it starts rather than in next month's meeting. The honest split: agencies win on big creative leaps and senior strategy; the department wins on the relentless daily operation of channels, which is where most SME marketing budgets actually leak.
What a retainer actually buys
Read your agency contract closely and it describes attention, not outcomes: a number of days or hours, a meeting cadence, a reporting rhythm. Within it, good people do good work, but the economics force batching. Your channels get thought about intensively for a few days a month and lightly the rest. The campaign launches, the meeting reviews it four weeks later, the fix waits for the sprint. Meanwhile the Tuesday problems, a creative fatiguing, a competitor bidding on your name, a landing page quietly broken since the CMS update, wait too, because per-day pricing cannot afford to check daily.
What the department does instead
Online Marketing is a set of AI specialists, paid ads, SEO, email, content, working as one team on your channels, every day. It watches spend and performance daily and rebalances inside the budgets and rules you set. It runs the boring, compounding tests (headlines, audiences, subject lines) continuously. It ships the email that should go out this week, in your voice, on time. It keeps SEO hygiene current and feeds findings to the Web Team if you run one. And it reports weekly in plain English: what was done, what moved, what it wants to try next, with anything sensitive queued for your approval first in AI Assisted mode. Ad spend above your thresholds always asks first; that rule does not relax with Autopilot.
The comparison, honestly
| Agency retainer | Online Marketing (AI) | |
|---|---|---|
| Typical cost | £2,000 to £10,000 a month | £229 a week (about £992 a month) |
| Working rhythm | Monthly cycles, meetings | Daily, continuous |
| Scope | Per contract, extras quoted | Ads, SEO, email, content as one team |
| Speed to react | Next meeting or a favour | Same day |
| Creative ceiling | High, their real strength | Competent and consistent, not campaign-of-the-year |
| Senior strategy | The good ones bring it | Executes your strategy, flags what it learns |
| Reporting | Monthly deck | Weekly plain-English page, live logs |
| Conflicts | You share the team with other clients | The department serves you |
The arithmetic
Take a firm spending £4,000 a month on a retainer plus £3,000 in ad spend. The retainer buys perhaps four to six senior-and-junior days across the month. The department at £992 leaves £3,000 of the difference in your pocket every month, or, better, reallocates it into the ad budget itself, and works the account thirty days instead of five. The fair challenge is quality: does daily competent beat monthly brilliant? For brand-defining creative, no, and we say so below. For the operational 80 per cent of SME marketing, budget hygiene, testing cadence, shipping consistency, daily beats monthly almost boringly, because most retainer underperformance is not bad ideas, it is good ideas executed late.
Where the agency wins
Keep, or hire, an agency when the job is a genuine creative leap: a rebrand, a launch campaign, an idea that needs award-level craft. Buy senior strategic counsel where it earns its rate: a fractional CMO or a strategist quarterly, setting direction the department then executes daily. If your category runs on relationships with media buyers or influencers an agency already owns, that access is real value. And if you have no idea what your positioning is, fix that first; no operator, human or AI, can drum a message that does not exist. Our own bias, stated openly: we would keep a strategist and a great creative on tap, and never again pay retainer rates for channel operation.
Frequently asked questions
How much does an AI marketing department cost compared with an agency?
Fortitude's Online Marketing department costs £229 a week, about £992 a month, billed monthly, cancel anytime. Mid-market UK digital agency retainers typically run £2,000 to £10,000 a month for a few working days of attention in monthly cycles. The department works your channels daily within the budgets and approval rules you set.
Does it replace our marketing agency?
It replaces the operational layer: daily budget management, testing, email shipping, SEO hygiene and reporting. It does not replace brand-level creative or senior strategy, and many clients keep a strategist or creative agency for exactly that while the department runs the channels. The wasteful pattern it ends is paying retainer rates for daily operations delivered monthly.
Who controls the ad spend?
You do, structurally. Budgets, thresholds and rules are set at onboarding; changes within them can run on Autopilot once you promote them, and anything above threshold always queues for approval, in every mode. Every change is logged with its reasoning, and the weekly report shows spend against results in plain English.
What channels does it cover?
Paid ads, SEO, email marketing and content, run as sub-specialists sharing one memory and plan, so the email list hears what the ads learned and the content answers what search and AI engines actually ask. It connects to the ad and analytics accounts you already run; nothing is rebuilt or migrated.
Can it work alongside our in-house marketer?
Well, and that is a common setup: your marketer sets direction and owns the brand, the department does the daily grind and hands them a weekly report plus an approval queue instead of a to-do list. One person with this department operates like a small team.