Google Ads Smart Bidding refers to the strategies where Google sets the bid for each auction based on the likelihood of conversion: target CPA, target ROAS, maximize conversions and maximize conversion value. Target CPA can start without conversion history. Target ROAS on Search and Shopping requires at least 15 conversions in the last 30 days and configured conversion values. None of them works if the conversion being measured is wrong.
This guide is for advertisers who already run campaigns and need to choose or change their bidding strategy. The requirements were checked in October 2026 in the Google Ads Help Center.
What Smart Bidding is in Google Ads
With Google Ads Smart Bidding, the bid is automatic and uses conversions as the goal. Google looks at signals from each search at auction time, such as device, location, time of day, remarketing list, language and operating system, and raises or lowers the bid based on how likely that person is to convert.
There are four strategies:
- Maximize conversions. Spends the entire budget aiming for the highest number of conversions.
- Target CPA. Aims for conversions while trying to keep the average cost per conversion at the target you set.
- Maximize conversion value. Spends the budget aiming for the highest total value.
- Target ROAS. Aims for value while trying to keep the return on ad spend at the target you set.
Since June 2026, Google has changed the names in the interface. “Maximize conversions with a target CPA” became just “Target CPA”, and “Maximize conversion value with a target ROAS” became “Target ROAS”. The behavior is the same.
Enhanced CPC was removed from Search and Display campaigns the week of March 24, 2025. Advertisers who didn’t migrate were moved to manual CPC.
How many conversions each strategy needs
Requirements change by strategy and campaign type. The table summarizes what Google documents.
| Strategy | When to use it | What Google requires |
|---|---|---|
| Maximize conversions | New account or volume goal | Conversion tracking set up |
| Target CPA | You know how much you can pay per lead or sale | Conversion tracking; can start without history |
| Maximize conversion value | Sales with different values | Conversion values configured |
| Target ROAS (Search and Shopping) | Store or business with measured revenue | 15 conversions in the last 30 days and a value greater than zero |
| Target ROAS (Demand Gen) | Demand Gen campaigns | 50 conversions in 35 days, 10 of them in the last 7 |
The ROAS figure comes from Google’s page on target ROAS bidding. The CPA figure is in target CPA bidding, where Google says you can start without history and that the strategy works for campaigns of all sizes.
A minimum requirement is not the ideal volume. With 15 conversions in a month, the algorithm has little to learn from, and each sale more or less moves the result a lot.
Target CPA: how to set the goal
Your CPA target comes from your margin, not from what the campaign did last month. Work backward: how much a customer is worth, how many leads become customers, and how much you accept paying per lead.
An example with round numbers. If 1 in 5 leads closes and you accept spending R$300 to win a customer, the maximum CPA per lead is R$60.
Now check that the target fits the click price. In our CPC survey by industry, the median across 103 industries was R$4.96, and the restaurant and delivery industry was R$1.45. This is the bid Google estimates for the top of the page in October 2026, not what each company pays. With a R$4.96 click and a R$60 target, the page needs to convert close to 1 in every 12 visits. If it converts 1 in 50, the target doesn’t work, and Smart Bidding will either hold back spend or exceed the CPA.
Three practical tips:
- Start with a target close to the real CPA of the last 30 days. A target far below it makes the campaign stop spending.
- Change the target in small steps and wait for the campaign to stabilize before the next change.
- Leave some budget room. Google notes that a day’s spend can reach up to twice the average daily budget, without going over 30.4 times that amount in the month.
Target ROAS: when your account is ready
Target ROAS works when the conversion carries the right value. For a store, that is the order revenue. For a service business, it is a value per funnel stage, which can come from the CRM.
Before you turn it on, check three things.
- The account has at least 15 conversions in the last 30 days, for Search and Shopping.
- Conversions have different values from one another. Google requires two or more distinct values before you can switch to a value-based strategy.
- The value is stable. If you just started sending value or changed how it is calculated, Google recommends waiting 1 to 2 conversion cycles before using Target ROAS.
Target ROAS on an account that sends the same value for every conversion becomes a Target CPA in disguise. The bid has no way to tell an R$80 order from an R$2,000 one.
For a service business, the value per stage comes from offline conversion tracking, when the CRM sends back who became a customer.
Maximize conversions: the most common starting point
Maximize conversions is the entry point to Google Ads Smart Bidding when the account doesn’t know its own CPA yet. The strategy tries to spend the full average daily budget. If the campaign had been spending well below budget, spend can jump all at once.
Two details in Google’s documentation catch a lot of people.
- Bid adjustments for location, time of day or audience stop applying. The only exception is the device adjustment of -100%, which still excludes the device.
- The Impression share lost (budget) column doesn’t fit this strategy, because it is built to spend the entire budget. Use the budget simulator.
When CPA settles at a level that fits your margin, the natural switch is to Target CPA, with the target close to that level.
2026 changes that affect bidding
Two Google changes in 2026 affect anyone using Target CPA or Target ROAS. The first is the rename we mentioned earlier. The second matters more.
Starting August 17, 2026, Google updated its bidding systems for budget-limited campaigns that use Target CPA or Target ROAS. Google itself warned that this may cause temporary fluctuations in performance and traffic, and on July 6, 2026 it released a bid target adjustment tool.
If your campaign with a target changed behavior starting in August and the budget was tight, start your investigation there, before touching ads or keywords.
Mistakes that block Google Ads Smart Bidding
Most Smart Bidding problems aren’t in the bidding. They are in what it receives as a conversion.
- Wrong primary conversion. WhatsApp clicks, contact page visits or scrolls counted as a primary conversion. The bidding learns to find people who click, not people who buy.
- Duplicate conversion. The same sale counted by the Google tag and by the imported GA4 conversion. CPA looks half of the real one.
- Impossible target. A Target CPA below what the click and the page allow. The campaign stops spending.
- Back-to-back changes. Changing target, budget and ad in the same week keeps the algorithm from stabilizing.
- Split volume. Ten campaigns with three conversions each, when a portfolio strategy would pool the signal.
- ROAS without real value. All conversions with the same value, or a lead value equal to a sale value.
If the campaign spends and doesn’t convert, the full diagnosis is in Google Ads not converting. To choose the campaign type before the bidding, see Google Ads campaign types.
How Ciclicko chooses the bidding
In Ciclicko’s management, the choice between Google Ads Smart Bidding strategies comes after checking the conversions. First we make sure the primary conversion is the one that generates revenue and that it isn’t duplicated. Then we pick the strategy based on the account’s real volume and set the target based on margin.
Elite Management includes two optimization rounds, on days 7 and 14, plus account setup, GTM, GA4 and conversions. The details are in Google Ads management, and pricing is sent on request. To get your quote, message us on WhatsApp.
Frequently asked questions
What is Target CPA in Google Ads? It is the Smart Bidding strategy where you set the average cost per conversion you are willing to pay, and Google adjusts the bid in each auction to get conversions close to that average.
Target CPA or Maximize conversions? Maximize conversions suits an account that doesn’t know its CPA yet, because it spends the entire budget. Once CPA settles at a value that fits your margin, Target CPA takes over cost control.
How do you set the Target CPA? Start from margin: customer value, lead close rate and how much you are willing to pay per customer. Start near the real CPA of the last 30 days and adjust gradually.
What is Target ROAS? It is the strategy where you set the return you want on spend, for example 400%, and Google adjusts the bid based on the predicted value of each conversion. For Search and Shopping, it requires 15 conversions in the last 30 days.
Which Smart Bidding strategy generates the most value? Maximize conversion value and Target ROAS are the ones that optimize for value. They only work well if conversions carry real values that differ from one another.
Get a free audit of your account
Before changing your bidding strategy, check that the conversion feeding the bidding is right. The free Google Ads audit analyzes accounts with a budget from R$1,000 per month and shows what to fix first.