Google’s Smart Bidding Update: Why the Cheapest CPL Isn’t Always the Best Lead

Every now and then, Google Ads drops an update that sets off a wave of panic across our industry. 

If you have been managing campaigns for a while, you know the drill: LinkedIn fills up with hot takes, strategy group chats go crazy and everyone starts questioning their entire setup. 

This time, it is a critical change to Smart Bidding for campaigns flagged as "Limited by budget": Google is changing how Target CPA (tCPA) and Target ROAS (tROAS) behave when your budget is capped. 

But if we look past the technical jargon, this update points to a truth that many media buyers tend to overlook: the cheapest lead is not necessarily the best lead. 

What actually changed in Smart Bidding?

To understand why people are talking about this, it helps to look at how things used to work. 

Previously, if you ran a campaign with a £35 Target CPA but your budget was limited, Google's algorithm could end up delivering conversions well below that target. You might set a £35 tCPA, for example, while seeing an actual average CPA closer to £20. 

Now, Google is changing that logic. 

Your bid target becomes a much stronger lever. If you tell Google that you are willing to achieve conversions at an average CPA of £35, the system has more room to pursue additional conversion volume rather than consistently favouring the cheaper auctions that were keeping your CPA well below target. 

That does not mean Google will pay exactly £35 for every lead. Target CPA is still an average target, not a hard ceiling for individual conversions. Some leads may cost significantly more and others significantly less. 

The important difference is that a campaign that previously delivered a £20 average CPA despite having a £35 target may now have more room to spend and pursue additional conversions, potentially pushing that average closer to the target you actually gave Google. 

Why media buyers aren't really panicking

When you first read the news, it sounds like a big shift. But for those of us who have spent years navigating Google's ecosystem, it comes as little to no surprise. 

The reality is Google is a business. Anyone who has managed budgets for years or spent time gracefully ignoring automated recommendations from Google Ads reps knows that Google's commercial incentives are not necessarily the same as your client's. 

Google wants advertisers to capture more available demand and use their budgets. Our job as media buyers is to make sure doing so also makes commercial sense for the business behind the account. That distinction matters. 

So rather than panicking about another Smart Bidding update, I would look at whether the bidding strategy you are using still supports the actual business objective: 

• Target CPA (tCPA): Still useful when you have a clear understanding of what you can afford to pay for a conversion. But if your target has been set artificially high because Google historically delivered well below it, it is worth reviewing. You may now be giving the algorithm considerably more room to pursue incremental conversions at a higher average cost. 

• Maximize Conversions (without a target): This can be worth testing when you would rather let Google maximize conversion volume within your available budget than anchor optimization to a specific CPA target. But it is not a shortcut to cheaper traffic. Google can still bid aggressively when it predicts a higher likelihood of conversion, so your daily budget and actual business outcomes still need to be monitored closely. 

What the account data is actually telling us 

When major updates like this drop, the natural instinct is to jump into accounts and start tweaking targets in a hurry. But whenever I audit high-spend accounts, the reality on the ground is usually very different from the industry noise. 

Looking across the accounts I currently manage, the immediate impact appears much narrower than some of the reaction to this update might suggest. 

There are a few clear reasons for this: 

1. Maximize Conversions 

A large portion of lead gen campaigns do not even use an explicit tCPA. If there is no Target CPA involved, this specific change to budget-constrained tCPA campaigns is not the immediate problem you need to solve. 

2. Budget constraints 

If your campaign uses tCPA but is not meaningfully limited by budget, this specific change is far less likely to affect it. Before changing anything, look at your own data. Check your

Search Lost IS (budget), campaign status, actual CPA versus target CPA and whether budget is genuinely restricting delivery. 

3. The real bottleneck 

Most of the time, the biggest problem in an account is not the latest algorithm update. 

It might be significant impression share lost to budget. It might be poor messaging. It might be weak landing pages. Or, particularly in lead generation, it might be a complete disconnect between what Google Ads calls a conversion and what the sales team actually considers a good lead. 

A £20 lead that never answers an email is not necessarily more valuable than an £80 lead that turns into a £5,000 customer. 

Which is why CPL alone should never tell the whole story. 

Exploring new channels and angles 

When a platform changes its rules, it is also a good reminder not to put all our eggs in one basket. Instead of only tweaking a bidding dial, it might be time to step back and look at the bigger picture. 

We live in an era where user behaviour is shifting fast. Between social media, generative AI and changing search habits, media buyers do not have to be locked into Google's ecosystem alone. 

AI and LLM platforms 

As people increasingly use conversational AI alongside traditional search engines, emerging advertising opportunities around AI and LLM-based platforms are worth watching and testing where they make sense. 

Being early also gives advertisers the opportunity to learn how users behave in these environments before they become as established and competitive as traditional paid search. 

Pre-qualify on social 

Channels like Meta, LinkedIn and TikTok give you much more room to experiment with creative, messaging and audience angles. Use that space to communicate who your product or service is actually for before someone clicks. 

The objective should not always be generating the maximum number of leads. Sometimes better advertising means deliberately making the wrong prospect scroll past. 

International competitors

Do not limit competitor research to the businesses bidding against you locally. Look at what brands in more mature or competitive international markets are doing. 

How are they positioning their offers? What pain points are they leading with? What are they doing on social that nobody in your market has tried yet? 

You may find much more interesting ideas there than in another round of keyword research.

Pre-qualify through messaging 

When faced with lower-quality leads, the traditional agency reflex is to add a ton of qualifying questions to the lead form. 

But let us be realistic: nobody wants to fill out a seven-field form on a mobile phone. Between privacy concerns and short attention spans, adding heavy form friction can easily kill your conversion rate without necessarily solving the underlying quality problem. 

Real qualification should not happen by interrogating the prospect at the end of the form. It should start much earlier through your copy, creative and offer. 

• Filter in the ad: Let your messaging do the heavy lifting. Focusing on a precise benefit, audience or condition can naturally attract the right buyer while making less relevant prospects scroll past. 

• Keep the form light: Ask only for what you really need to start a conversation, like a name and an email. Who even uses phone calls in 2026, anyway? 

• Close the loop with your CRM: Instead of making the user do all the work, connect your CRM back to Google Ads using Offline Conversion Tracking (OCT). By sending meaningful sales milestones back to Google, such as qualified leads or closed deals, you give the algorithm a much stronger signal than a simple form submission. 

If Google only knows that someone completed a form, it will optimize for more people who complete forms. If Google knows which of those people eventually became qualified opportunities or customers, you are giving Smart Bidding something far more valuable to learn from. 

A simple checklist 

If you are managing lead gen campaigns right now, here is how I would approach this: 

• Audit before you edit: Check whether you actually have campaigns labelled as Limited by budget using tCPA and delivering below their targets. Then ask whether that Target CPA still reflects what a conversion is genuinely worth to the business. 

• Do not optimize around CPL alone: Compare lead volume and CPL with qualified lead rate, cost per qualified lead and, where possible, actual revenue. A cheaper lead is irrelevant if it never becomes a customer. 

• Give it time: Do not judge performance after three days. Allow enough time to cover at least one or two full conversion cycles before drawing conclusions from a bidding change.

• Close the data loop: If Google Ads is optimizing towards form submissions while your CRM knows which leads actually generate revenue, connect the two. ● Keep calm and diversify: Do not make reactive changes because of one Google update. Use it as a nudge to refine your messaging, improve your conversion data and explore channels and creative angles outside of Google. 

Our job as media buyers is to make sure Google is not simply optimizing towards a conversion, but towards the conversions that actually matter to the business.