Google Ads Customer Acquisition: Are We Bidding on Profit or Hope?
Google Ads will happily let you tell its bidding system that a customer who spends £100 is worth £150. Lovely. Now show me where the extra £50 is coming from.
Before anyone gets upset, I understand that customer lifetime value (CLV) is a thing. I understand why acquiring a new customer might be worth more than generating another order from someone who has bought from you 15 times. And I am certainly not suggesting we should only optimise for immediate returns.
But I do think we are becoming a little too comfortable putting numbers into bidding algorithms without properly understanding what those numbers mean for the business. There is a fairly important distinction between what a customer might be worth in the future and what they have actually contributed today.
If we are not careful, we can make Google Ads reporting look healthier without the underlying commercial performance improving at all.
How does Google Ads customer acquisition bidding work?
Google Ads customer lifecycle goals allow advertisers to prioritise new customers and, in supported configurations, attach additional conversion value to acquiring them. There is a sensible reason for this: an automated bidding system that only sees the first transaction may undervalue customers who go on to make profitable repeat purchases.
Take a deliberately simple example. A new customer places a £100 order. An advertiser assigns £50 of additional new-customer value. The value used for bidding may be £150, although the actual purchase revenue remains £100. The extra £50 is a modelling decision, not another £50 paid into the bank.
The precise reporting depends on the lifecycle goal and conversion columns being used. That is exactly why PPC practitioners need to understand the distinction rather than assuming every conversion-value figure represents transaction revenue.
Customer lifetime value is not customer profit
This is where things get interesting. A customer spends £100 today and another £200 over 12 months, so their projected lifetime revenue is £300. Brilliant. Except we have skipped over the costs of earning those sales.
Imagine two customers. These figures are illustrative, with contribution calculated after relevant variable trading costs but before acquisition advertising cost.
Metric | Customer A | Customer B |
First purchase | £100 | £100 |
Subsequent revenue | £200 | £100 |
Lifetime revenue | £300 | £200 |
Contribution margin | 15% | 40% |
Lifetime contribution before acquisition cost | £45 | £80 |
Customer A looks more valuable if we only examine revenue. Customer B actually produces more contribution. So which should Google try to find more of? The answer should reflect contribution after acquisition cost and the business’s objectives, not simply the largest top-line total.
Why customer acquisition value can make ROAS misleading
Suppose a campaign spends £1,000, generates £4,000 of actual purchase revenue and reports an additional £1,000 of acquisition value. Actual revenue divided by spend is 400%. Adjusted conversion value divided by spend is 500%.
Neither calculation is automatically wrong. They answer different questions. Trouble starts when somebody presents the adjusted 500% as though it were £5,000 in actual sales, uses it to justify extra spend, or compares it uncritically with periods before the adjustment.
The Google Ads number has improved. The business has not necessarily made another penny. This is not an accusation that Google is hiding anything; it is our responsibility to choose appropriate reporting columns and explain them accurately.
How should PPC managers calculate acquisition value?
I would start somewhere different from the Google Ads interface. I would start with the business.
1. Check actual repeat purchase behaviour
How many customers return, how quickly, and what do they buy? Use real cohorts, not the optimistic average in a slide deck. People acquired during a deep-discount clearance event may behave differently from full-price shoppers. Grouping them together can produce a misleading estimate.
2. Work from contribution, not turnover
Include product cost, discounts, fulfilment, payment costs, expected returns and other relevant variable expenses. Then evaluate acquisition spend separately. You may not have perfect SKU-level financial data; an honest, conservative estimate is still better than treating all revenue as equally valuable.
3. Ask when the cash comes back
Two customers could have the same forecast lifetime contribution but very different payback periods. One pays back in 30 days; the other takes nine months. For a retailer with cash tied up in stock and suppliers to pay, those are not necessarily equivalent acquisitions. Profitable eventually and affordable today are two different things.
4. Stress-test the assumption
Lifetime value is a forecast, not a certainty. Check what happens if repeat purchase rates, margins or returns turn out worse than expected. If the evidence is weak, start conservatively, test and revise. There is nothing wrong with testing a hypothesis. There is something wrong with presenting one as a fact.
A practical five-step framework
Calculate future revenue from comparable acquisition cohorts, not just an account-wide average.
Estimate contribution from future purchases after relevant variable costs.
Factor in payback time, working capital pressure and forecast uncertainty.
Agree a defensible acquisition value with ecommerce and finance stakeholders.
Test and reconcile Google Ads bidding/reporting values against actual trading outcomes.
If you cannot explain the value adjustment clearly to a commercial director, it is probably worth reviewing before you feed it into a bidding strategy.
Should you always bid more for new customers?
No. It depends. A retailer with strong repeat behaviour, healthy contribution, reliable data and comfortable cash reserves may sensibly prioritise customer acquisition. Another with ageing inventory, supplier commitments and immediate cashflow pressure might not.
A setting in Google Ads can help execute the strategy. It cannot choose the business strategy for you.
The questions I wish more PPC teams asked
What do these customers actually contribute after variable costs?
How long does it take to recover acquisition investment?
Are sale-acquired customers worth as much as full-price customers?
Does the business need growth, contribution or cash released from stock right now?
What would change our decision if our CLV assumptions were wrong?
These are not questions every PPC practitioner is expected to answer alone. They are questions we should get comfortable asking. With bids, placements and targeting increasingly automated, our commercial judgement matters more, not less.
Conclusion: do not confuse a bidding signal with money in the bank
I am a fan of giving Google better signals. If your lifetime value data is reliable, use it. If acquiring certain customers delivers more sustainable profit, reflect that in your strategy. But challenge the assumptions first.
A £100 order can be assigned £150 of value in an advertising platform. It does not mean £150 arrived in the bank. You need to know where the extra value comes from, when it should materialise and whether the business can afford to invest to capture it.
Otherwise, we are not really optimising for customer lifetime value. We are optimising for hope. And hope is a pretty expensive bidding strategy.
References and editor notes
Editor note: All numerical examples are hypothetical. One supplied PNG is available for insertion at the indicated point. No client data or screenshots are used.
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