This article is written for CFOs and finance directors who are trying to understand what marketing attribution is, why their CMO keeps talking about it, and whether the marketing budget is actually working. It is not written for marketers. It covers the attribution problem in commercial terms, what the different models actually tell you, and what a CFO should expect from a marketing team that is doing attribution properly.

The attribution problem in plain terms

Your marketing team spends £500,000 this year on content, paid advertising, events, and software. In the same year, the business generates £8M in new ARR. How much of that £8M came from marketing? How much came from sales? How much came from product, reputation, or referrals?

Marketing attribution is the set of methods used to answer that question. The honest answer is that no method is perfectly accurate — but some methods are significantly more informative than others, and a business operating with no attribution at all is making marketing investment decisions based on guesswork.

The question is not "did marketing contribute to revenue?" — in almost every B2B company it did. The question is "by how much, through which activities, and what should we invest more or less in as a result?"

£1.8M Average marketing-influenced revenue identified in the first attribution report for companies with no prior attribution infrastructure, based on Harmonic programme data. In most cases this revenue was already in the CRM — it was simply invisible because the infrastructure to see marketing's contribution did not exist.

Why your CMO struggles to answer your attribution questions

When you ask "what did we get from the £500k we spent on marketing?" and your CMO gives an unsatisfying answer, it is usually because of one or more of three genuinely difficult technical problems — not because they are hiding something or don't know what they're doing.

1
The B2B buying journey involves 6-15 touchpoints across 6-18 months

A buyer who closes in October may have first encountered your brand through a LinkedIn post in January, attended a webinar in April, downloaded a case study in July, searched Google in September, and booked a demo after seeing a retargeting ad in October. Which of those touchpoints does marketing get credit for? All of them? Just the last one? This is not a philosophical question — it determines where marketing budget goes next year.

2
Some of the most valuable marketing channels leave no digital footprint

A buyer who heard about your company from a peer at an industry conference, thought of you when a buying trigger occurred, and searched your brand name on Google before booking a demo — will appear as a branded search conversion in your CRM. The conference conversation is invisible. Word of mouth, analyst mentions, LinkedIn posts that were read but not clicked — all of these drive pipeline without leaving a trackable trail in standard digital attribution systems.

3
Standard CRM attribution defaults to last-touch, which systematically misleads

Out of the box, HubSpot, Salesforce, and most CRMs attribute 100% of conversion credit to the last touchpoint before a contact became a lead. For a buyer who was nurtured for 12 months, this means Google Search or Direct Traffic gets all the credit — because the buyer came back to your site via search on the day they decided to book a demo. This is not wrong because marketing made a mistake. It is wrong because the attribution model is wrong.

What good marketing attribution looks like from a CFO perspective

A marketing team with mature attribution produces three things that a CFO can use for decision-making.

1. Pipeline ROI by channel
Where each £1 of spend goes furthest

A monthly report showing the pipeline generated per £1,000 of spend by channel — LinkedIn, Google Search, content and SEO, events, retargeting. This tells you not just what marketing spent, but what each spending category produced. A channel with a pipeline ROI of 4× should receive more budget. A channel at 0.5× should be investigated or cut. This is the single most useful output of an attribution programme for budget decisions.

2. Marketing-influenced pipeline
Marketing's contribution to deals closing

The total pipeline value of deals in which marketing had at least one touchpoint in the 90 days before the opportunity was created. This is typically 2-4× larger than "marketing-sourced pipeline" (deals where marketing was the first touchpoint) and better reflects marketing's actual contribution to revenue. A well-functioning B2B marketing programme typically influences 40-60% of total pipeline even when it directly sources 20-30%.

3. Marketing CAC and payback period
The unit economics of customer acquisition

Marketing Customer Acquisition Cost is total marketing spend divided by customers acquired through marketing-influenced deals in the period. Payback period is marketing CAC divided by monthly revenue per customer multiplied by gross margin. These are the metrics that connect marketing spend to financial returns in terms that translate directly into investment decisions.

4. Self-reported attribution
What customers say drove them to you

"How did you first hear about us?" on every demo request form, discovery call, and onboarding survey. Self-reported data is imperfect — buyers have imperfect recall — but it captures channels that digital tracking misses entirely: word of mouth, events, podcast mentions, LinkedIn posts. Comparing self-reported data against digital attribution data reveals the gap between what the tracking shows and what actually happened.

Questions to ask your CMO about attribution

If you are a CFO evaluating whether your marketing team has adequate attribution infrastructure, these questions will quickly surface the answer.

The attribution questions every CFO should ask
  • "What attribution model do we use, and why did we choose it?" A CMO who cannot answer this question — or who says "last touch" without acknowledging its limitations — does not have a mature attribution programme. The right answer includes the model name, why it was chosen for your specific sales cycle, and what its known limitations are.
  • "What is our pipeline ROI by channel?" If the answer is a single blended number ("we generate £2.50 of pipeline per £1 of marketing spend") rather than a breakdown by channel, the attribution is not granular enough to make investment decisions. You need to know which channels are producing the return, not just the average.
  • "What percentage of our closed-won deals in the last 12 months had a marketing touchpoint?" This is marketing-influenced pipeline as a percentage of total revenue. A well-functioning B2B marketing programme should influence 40-70% of new ARR, depending on your sales model. Significantly below 40% suggests the marketing programme is not reaching buyers effectively, or attribution is undercounting.
  • "Where is our attribution measurement weakest and what would it cost to fix it?" This question reveals whether your CMO has a realistic view of their measurement limitations. A good answer identifies specific gaps (dark funnel channels, offline event attribution, multi-device tracking) and has a view on what infrastructure investment would be required to address them. There is no perfect attribution — but there is better and worse, and a good CMO knows the difference.
Key takeaways