Google Ads Bidding Strategies: When to Use Target CPA, Target ROAS, Maximize Conversions or Maximize Conversion Value
Google Ads smart bidding has become the standard way to manage bids, and for most advertisers it outperforms manual bidding. The bigger question is which bid strategy to use, and when.
Across our client accounts, which span e-commerce, B2B, lead generation, hospitality and nonprofits, we regularly see campaigns held back by a bid strategy that is a poor fit for where the account is today. A new campaign running Target ROAS with only a few conversions a month. An e-commerce store on Maximize Conversions, where a $12 order counts the same as a $1,200 order. A lead gen campaign with a Target CPA set so low that it barely spends.
Below, we break down the four Google Ads bidding strategies we use most: Maximize Conversions, Maximize Conversion Value, Target CPA and Target ROAS. We cover when each one makes sense, what to watch out for, and how we move accounts from one strategy to the next. This post focuses on smart bidding only, so manual CPC and Maximize Clicks are left out.
Start With Your Conversion Data
Smart bidding is only as good as the conversion data behind it. Google sets a bid for each auction based on how likely that search is to convert, so if your tracking counts the wrong actions, the algorithm will optimize toward the wrong actions.
Before changing any bid strategy, we check three things:
Primary conversion actions reflect real business results, such as purchases, demo requests or qualified leads. Page views, scroll depth and newsletter signups should be set as secondary so they stay out of bidding decisions.
Conversion values are accurate. For e-commerce, that means actual order revenue passed dynamically. For lead gen, that means assigned values by lead type or, better yet, values imported from your CRM.
There is enough conversion volume. The more conversions a campaign records, the faster and more accurately smart bidding learns. Campaigns with only a handful of conversions per month will see bigger swings regardless of the strategy.
If any of these need work, fix them first. A new bid strategy can only work with the data it receives.
Maximize Conversions: Best When Conversion Data Is Limited or for Small Budgets
Maximize Conversions tells Google to get as many conversions as possible within your daily budget. It has no cost target, so it will spend the budget and focus on volume.
We use Maximize Conversions for most new campaigns and for accounts with limited conversion history. It needs less data than the target-based strategies because its only goal is to find more conversions, and every conversion it records helps it learn.
Maximize Conversions is a good fit when:
The campaign is new or was recently restructured.
The campaign has low monthly conversion volume and needs to build data.
Each conversion is worth about the same to the business, such as a lead gen account with one main form.
You are working with very limited budgets.
What to watch: cost per conversion can rise over time since nothing is holding it in check. Maximize Conversions will also use your full daily budget. We recommend monitoring CPA week over week and treating this strategy as a starting point.
In Search campaigns, Target CPA is now an optional setting within Maximize Conversions. When you're ready for more control, you can add a target CPA to the same strategy.
Maximize Conversion Value: For E-commerce and Lead Gen With Offline Data
Maximize Conversion Value focuses on revenue. It aims for the highest total conversion value within your budget and will bid more for searchers who are likely to place larger orders.
For e-commerce advertisers, this is usually the right choice once revenue tracking is in place. A store selling $40 accessories alongside $900 machines needs a strategy that values those sales differently, and Maximize Conversions treats every sale the same.
For lead generation, Maximize Conversion Value works best when offline data is in place. That means importing what happens after the form fill, such as which leads became MQLs, SQLs or closed deals, and what each one was worth. With that data, Google can learn to tell a lead that turns into a $50,000 contract from one that goes nowhere.
Maximize Conversion Value is a good fit when:
You run an e-commerce account with dynamic revenue tracking.
You run lead gen with offline conversion imports or enhanced conversions for leads, along with real values from your CRM.
Your products or services vary widely in value.
What to watch: like Maximize Conversions, this strategy has no efficiency guardrail. It will use the full budget, and ROAS can slip. Once you have steady conversion value data, we usually recommend adding a Target ROAS.
Target CPA: When You Need a Specific Cost Per Acquisition
Target CPA tells Google how much you want to pay per conversion, and it aims to get as many conversions as possible at or near that average. It is the go-to bid strategy for lead gen accounts with clear numbers. If your sales team values a lead at $150, Target CPA lets you bid toward that figure.
The challenge is setting the right target. If the target is too low, Google will only enter auctions where it expects to convert cheaply. Impressions drop, budget goes unspent, and conversions can fall below where they were before. We see this often: a client wants a $40 CPA on a campaign that has been running at $85, and the campaign slows down almost overnight.
Here's how we approach Target CPA:
Start close to your actual CPA from the last 30 days and work toward your goal from there.
Allow about two weeks for the learning period before evaluating results.
Lower the target in small steps, around 10 to 15% at a time, and watch impressions and spend after each change.
If spend drops and impression share lost to rank climbs, the target is too tight. Raise it back up.
Target CPA is a good fit when you have consistent conversion volume, a clear cost you can afford per lead or sale, and conversions of similar value.
Target ROAS: The Efficiency Play
Target ROAS works like Maximize Conversion Value with a guardrail. You set the return you want, for example 400% ($4 in revenue for every $1 spent), and Google bids to hit that average while still pursuing high-value conversions.
In our experience, Target ROAS almost always outperforms Maximize Conversion Value on efficiency. Maximize Conversion Value will use the full budget to chase revenue, while Target ROAS keeps spending tied to a return you can live with. For most of our e-commerce clients, adding a ROAS target is where profitability starts to improve.
The trade-off is reach. If the target is too aggressive, Google will skip auctions where it can't reach your number. Impressions shrink, spend drops, and you may end up with a strong ROAS on far less revenue. A 900% ROAS on $2,000 in sales is a step backward from a 450% ROAS on $20,000.
Here's how we approach Target ROAS:
Start at or slightly below the ROAS the campaign has averaged over the last 30 days.
Allow about two weeks for the learning period before making changes.
Raise the target in small steps and track total revenue alongside ROAS.
If revenue and impression share fall, the target is too aggressive. Bring it down.
Target ROAS is a good fit when you have reliable conversion values, enough data for the campaign to learn from, and a clear return you need to stay profitable. Like Target CPA, in Search campaigns it is now an optional setting within Maximize Conversion Value.
Google Ads Smart Bidding Strategies at a Glance
Bid strategy | Optimizes for | Best for | Data needed | Main risk |
Maximize Conversions | Number of conversions | New campaigns, low conversion volume | Low | CPA creeps up, full budget spent |
Maximize Conversion Value | Total conversion value | E-commerce, lead gen with offline data | Medium, with accurate values | ROAS slides, full budget spent |
Target CPA | Conversions at a set cost | Lead gen with a known cost per lead | Steady conversion volume | Target too low limits impressions |
Target ROAS | Conversion value at a set return | E-commerce and value-based lead gen | Steady volume and reliable values | Target too high limits reach |
How We Move Accounts From One Bid Strategy to the Next
Choosing a bid strategy is an ongoing process. Most of our accounts move through these stages as they build data:
Launch on Maximize Conversions to build volume and give smart bidding data to learn from.
Once conversions are steady, add a Target CPA based on what the campaign is already achieving.
If conversions vary in value, switch to Maximize Conversion Value. For lead gen, wait until offline conversion imports are running.
When value data is reliable, add a Target ROAS and tighten it gradually.
Some accounts stay at step 2 for good. A lead gen client with one service and one form may run on Target CPA long term, and that works well. The goal is to match the strategy to the business.
When you do switch, change one thing at a time. If you launch a new bid strategy, a new target, a budget change and a new landing page in the same week, it becomes very hard to tell what drove the results.
Common Bid Strategy Mistakes We See in Account Audits
These issues come up in many of the accounts we take over:
Setting targets based on goals instead of history. Start from what the campaign is achieving today and move toward the goal over time.
Judging results too early. The first week after a bid strategy change can be noisy, so give it the full learning period.
Changing targets every few days. Large changes reset learning. Small adjustments spaced out over time work better.
Optimizing toward soft conversions. If "viewed pricing page" is a primary conversion, smart bidding will look for more people who view the pricing page.
Using Maximize Conversion Value for lead gen without CRM data. Google needs tiered lead values to tell strong leads from weak ones.
Overlooking budget limits. If a campaign is limited by budget, review the budget before adjusting your CPA or ROAS target.
Frequently Asked Questions
What is the best Google Ads bidding strategy?
The right strategy comes down to how much data you have and what you're optimizing for. Maximize Conversions is best for new campaigns with little data. Target CPA fits lead gen with a known cost per lead. Maximize Conversion Value and Target ROAS fit e-commerce and lead gen accounts that track real conversion values.
Is Target ROAS better than Maximize Conversion Value?
For efficiency, usually yes. Target ROAS keeps spending tied to a return you can live with, while Maximize Conversion Value spends the full budget. The risk is setting the ROAS target so high that the campaign loses reach.
Why did my impressions drop after I set a Target CPA?
The target is probably too low. Google is only entering auctions where it expects to convert at that cost. Raise the target closer to your recent average CPA and lower it gradually.
How long should I wait after changing my bid strategy?
Give it about two weeks for the learning period, longer for low-volume campaigns or long sales cycles. Avoid other big changes during that time.
Can I use Maximize Conversion Value for lead generation?
Yes, if you import offline conversion data from your CRM with real values. Until offline data is in place, Target CPA or Maximize Conversions is usually the better choice.
Need Help Choosing a Bid Strategy?
If your campaigns are spending without results or are held back by a target that's too tight, the bid strategy is one of the first places we look. We'll review your conversion tracking, smart bidding setup and targets, and share what we'd change and why.
If you need a sanity check from a Google Ads expert, we'd be happy to chat and help you figure out which bid strategy makes sense for your account. Book a free consultation to get started.
