The affiliate channel should be your most profitable.
For most brands, it isn't.

UK affiliate marketing agencies typically charge £1,000–£10,000 per month, depending on programme size and scope. The wide range reflects two real differences: how mature the programme is, and what's included in the remit.

Two things every prospective client should ask before signing with any affiliate agency. First, what's the total cost of running the programme — not just the agency fee, but the network fees, publisher commission payouts, override charges, and any optional spend like tenancy fees for premium placements. Surprises here are how agency relationships go wrong. Second, are agency incentives aligned with yours — are they paid more when the programme grows efficiently, or simply when it grows at any cost?

Glass Digital prices on programme size and scope, transparently quoted against your actual programme. The free audit is the natural place to walk through the full cost picture — fees, network costs, expected commission spend, and where optional spend like tenancies might genuinely earn their keep — so you can compare like-for-like against any other agency you're considering.

This is the most common — and most legitimate — concern about affiliate marketing. The honest answer: cannibalisation happens in badly-managed programmes, and it's exactly the problem proper affiliate campaign management is designed to solve.

Three things prevent it: voucher suppression rules so partners can't claim a sale when the user searched for "brand + voucher" at checkout; commission structures weighted by partner type so cashback isn't paid the same as content publishers driving genuinely new traffic; and incrementality testing to identify which partners drive new customers vs. existing ones. Programmes we audit regularly find 15–30% of paid commission was on cannibalised sales — that's the work.

The bigger answer is that a good affiliate programme isn't just cashback and voucher. It's content publishers, closed user groups (Blue Light Card, KidStart), influencers, comparison sites, CSS partners — partner types that introduce your brand to audiences your paid channels can't reach. CJ Affiliate's incrementality study across 21 million shoppers found affiliate-acquired customers deliver 88% higher revenue per shopper than other channels, which is the opposite of cannibalisation.

For new programmes, the foundations are typically in place within 30–60 days, with measurable revenue within 90 days. Programmes scaling toward the 10–15% revenue-contribution benchmark usually take 6–12 months — that's a generalisation, but it reflects the reality that compound growth comes from sustained partner recruitment, commission optimisation and seasonal campaign timing, not from the initial launch.

For existing programmes that we take over, the timeline is different. Quick wins (commission restructuring, attribution fixes, lapsed partner reactivation) often deliver impact within the first quarter. Structural changes — diversifying into new partner types, migrating networks — are 3–6 month projects with compounding upside.

What we won't do is promise specific results inside specific timeframes for your business sight-unseen. Anyone quoting "X% growth in Y days" without seeing your programme is either guessing or selling. The audit is a more honest way to set expectations.

It depends on your programme's stage and your team's bandwidth. A dedicated in-house affiliate manager typically costs £45,000–£70,000 per year plus tooling and network fees — workable economics if your programme is large enough to justify a full-time hire, harder if you're under £5m online revenue and the role would absorb maybe 30% of someone's time alongside other duties.

An affiliate marketing agency makes sense when you want senior expertise without a full-time hire, when you need access to relationships with networks and partners that take years to build internally, or when the programme needs strategic restructuring rather than steady-state management. The right comparison isn't agency vs in-house cost — it's agency cost vs the revenue uplift from doing the channel properly, which for most ecommerce brands is many multiples of agency fees.

The wrong answer is hybrid in name only — an agency that does the bare minimum while an in-house person also half-manages it. Pick a model and resource it properly.

It depends on your sector, your scale, your tracking sophistication, and which partners are critical to your category. Awin is dominant in the UK with strong publisher coverage; CJ has deeper enterprise tooling and a stronger US partner base; Impact is the technology leader for sophisticated attribution and partnership types beyond traditional affiliate; Rakuten Advertising leans premium retail; Partnerize and Webgains have specific strengths in different verticals.

Glass Digital is platform-agnostic — we run programmes across all six and recommend based on your business, not commercials. We're also experienced at managing migrations end-to-end when the network you're on is the wrong fit, so this question doesn't have to be permanent. The right choice for a £2m fashion brand launching is rarely the right choice for a £30m homeware brand restructuring an existing programme. The audit looks at this specifically.

Daily affiliate program management is less glamorous than agency websites suggest, and that's the point — it's the unglamorous work that compounds. A typical week involves partner recruitment outreach, commission tier optimisation by partner type, validating transactions to protect cost of sale, attribution rule maintenance, lapsed partner re-engagement, weekly performance review against forecast, seasonal campaign planning ahead of trading peaks, and competitive intelligence on what your direct competitors are running.

Strategic work happens monthly and quarterly — performance reviews, partner mix decisions, commission restructures, network reviews, incrementality analysis. Reporting is delivered as a working document used in conversation, not a PDF nobody opens.

The work that doesn't fit on a deliverables list but matters most: relationships with the partners that move revenue. The top performers in your category get pitched constantly. Whether they pick up your call when you need a Black Friday slot is the difference between a good programme and an average one.

It shouldn't, if the transition is run properly. The first 30 days of any agency switch should be diagnostic, not disruptive — understanding what's working before changing what isn't. Existing partner relationships continue uninterrupted, existing commission structures stay in place, and we audit before we touch anything. Changes happen in week 4–8 once we've earned the right to make them.

What we'll usually find is a mix: some things working well that should continue, some quietly leaking margin or cannibalising other channels that need restructuring, and significant gaps in partner coverage that the previous agency didn't fill. The audit is the document we work from — and we share it with you in full whether you hire us or not.

The riskier transition isn't agency-to-agency, it's network-to-network. Where a network migration is genuinely the right call, we project-manage it end-to-end with no in-house lift required.

Affiliate marketing works for ecommerce brands across a wide range — but the economics shift at different stages. Below roughly £500k online revenue, the network fees and management overhead can be hard to justify unless your margins are strong; lighter-touch tools or in-house management often make more sense at this stage.

The sweet spot for agency-managed programmes is £1m–£50m+ online revenue, where the channel can realistically contribute 10–15% of online revenue at a healthy cost of sale, and where the strategic complexity (partner mix, commission structures, attribution) genuinely needs senior expertise to manage. Above £50m, in-house teams become viable, often working with an agency in a specialist capacity rather than full management.

Sector matters too. Affiliate works particularly well in considered-purchase categories where buyers research — home, beauty, fashion, baby, B2B services, specialist retail. It works less well in pure-impulse categories or markets where the purchase decision is dominated by a single distribution channel. The free audit is the cheapest way to find out which side of the line you're on.