Google Ads Bidding Strategies Explained Simply

Why Your Bidding Strategy Matters

Your bidding strategy tells Google how to spend your money. Choose the wrong one, and you'll either overpay for clicks, miss out on valuable traffic, or let Google's automation run wild with your budget.

The right strategy depends on where you are in your Google Ads journey — specifically, how much conversion data your account has. This guide explains each option in plain English and tells you exactly when to use it.

The Four Main Bidding Strategies

1. Manual CPC (Cost Per Click)

What it does: You set the maximum amount you're willing to pay for each click, for each keyword. Google won't charge you more than your max CPC, though you'll often pay less.

How it works in practice:

You have complete control. If a keyword is too expensive, lower the bid. If you want more traffic on a high-performing keyword, raise it.

When to use it:

• When you're just starting out and have little or no conversion data
• When you want full control over what you pay for each keyword
• When managing a small account where you can monitor individual keywords

Pros:

• Complete control over costs
• No surprises in your spend
• Good for learning how the auction works

Cons:

• Time-consuming to manage as your account grows
• You might bid too low on valuable keywords or too high on poor ones
• Doesn't adapt automatically to changes in competition or search behaviour

Tip: Enable "Enhanced CPC" as a stepping stone — this lets Google adjust your manual bids slightly up or down based on the likelihood of a conversion. It's a gentle introduction to automation without losing control.

2. Maximise Clicks

What it does: Google automatically sets your bids to get as many clicks as possible within your daily budget. You can set a maximum CPC limit to cap individual click costs.

How it works: Google's algorithm adjusts your bid for each auction to win as many clicks as your budget allows. With a £20 daily budget and a £3 max CPC, Google will try to get as many clicks as possible at or below £3 each.

When to use it:

• When you're starting a new campaign and need traffic to gather data
• When your goal is visibility and you don't have conversion tracking set up yet
• As a temporary strategy while building toward enough data for smarter bidding

Pros:

• Simple to set up
• Gets traffic flowing quickly
• Good for data gathering

Cons:

• Optimises for clicks, not conversions — you might get lots of clicks that don't convert
• Without a max CPC limit, Google can spend heavily on individual clicks
• Doesn't consider the quality or intent behind each click

Important: Always set a maximum CPC limit when using this strategy. Without it, Google might spend £15 on a single click if it thinks it can win the auction.

3. Target CPA (Cost Per Acquisition)

What it does: You tell Google how much you want to pay per conversion (e.g., per phone call or form submission), and Google automatically adjusts your bids to hit that target on average.

Example: If your target CPA is £30, Google will bid higher for searches that are likely to convert and lower (or not at all) for searches that aren't. Some conversions will cost more than £30, some less — but the average should be around your target.

When to use it:

• When you have at least 30 conversions in the last 30 days (Google's recommended minimum)
• When you have reliable conversion tracking set up and know what a good cost per lead looks like
• When you know what a lead is worth to your business

How to set your target CPA:

Example: If your average customer is worth £500, you close 1 in 5 leads, and you want a 3x return on ad spend:

• Value per lead = £500 x 20% = £100
• Target CPA = £100 / 3 = ~£33

Pros:

• Highly effective when it has enough data
• Saves significant management time
• Adapts to changes in competition and search behaviour automatically

Cons:

• Needs substantial conversion data to work properly
• Can reduce traffic volume if your target is too aggressive
• Less transparent — you can't see exactly what Google bids for each keyword

Common mistake: Setting your Target CPA too low. If you've been averaging £40 per conversion and set a target of £20, Google will drastically reduce your traffic to hit that target — often resulting in very few conversions at all. Start with a target close to your current average, then gradually reduce it.

4. Target ROAS (Return on Ad Spend)

What it does: You set a target return on ad spend (as a percentage), and Google adjusts bids to achieve that return. This requires conversion values to be tracked.

Example: A target ROAS of 500% means you want £5 in revenue for every £1 spent on ads.

When to use it:

• When you track conversion values (not just conversion counts)
• When different conversions have meaningfully different values
• When you have a large enough volume of conversions with values (typically 50+ per month)

Pros:

• Optimises for revenue, not just conversions
• Ideal for businesses where lead values vary significantly
• Sophisticated automation that considers value, not just volume

Cons:

• Requires accurate value tracking — if your values are wrong, the automation is wrong
• Needs high conversion volumes to work effectively
• Most UK small businesses don't have enough data to use this strategy well

Our recommendation: For most small to medium UK businesses, Target CPA is a better fit than Target ROAS. Target ROAS is best suited to e-commerce or businesses with significant variation in deal sizes and high conversion volumes.

Choosing the Right Strategy: A Decision Framework

How to Switch Strategies Safely

Changing your bidding strategy can cause a temporary dip in performance while Google's algorithms adjust. Here's how to minimise disruption:

Moving From Manual CPC to Target CPA

1. Ensure conversion tracking is solid. Verify it's been recording accurately for at least 30 days. Dodgy data will lead to dodgy automation.

2. Calculate your current CPA. Look at your average cost per conversion over the last 30-60 days.

3. Set your initial Target CPA at or slightly above your current average. Don't try to improve immediately — let the algorithm learn first.

4. Allow a 2-week learning period. Performance may fluctuate. Resist the urge to change things during this time.

5. Gradually reduce your target. Once performance stabilises, lower your Target CPA by 10-15% increments every 2 weeks.

Moving From Maximise Clicks to Target CPA

Follow the same process, but expect a bigger adjustment period. The algorithm is shifting from optimising for clicks to optimising for conversions — it needs time to learn which clicks convert.

Bidding Strategy Mistakes to Avoid

Setting Target CPA Too Aggressively

If your current CPA is £45 and you set a target of £20, Google will struggle to find enough conversions at that price. Your traffic will drop dramatically, and you might end up with fewer conversions at a higher actual CPA.

Switching Strategies Too Frequently

Every time you change strategy, Google's algorithm starts learning from scratch. Give each strategy at least 2-4 weeks before evaluating.

Ignoring the Data Requirements

Target CPA with 5 conversions per month isn't Target CPA — it's guesswork. You need consistent volume for automation to work. If you don't have it, stick with manual control.

Forgetting to Set Maximum CPC Limits

With Maximise Clicks, always set a max CPC. Without one, Google can (and will) spend disproportionate amounts on individual clicks.

Not Monitoring After Switching

Automated bidding doesn't mean "set and forget." Check performance weekly to ensure the algorithm is delivering results within acceptable parameters.

The Bigger Picture

Your bidding strategy is one piece of the puzzle. It works alongside your keyword selection, ad copy, landing pages, and account structure. The best bidding strategy in the world won't save a campaign with poor fundamentals.

Not Sure Which Strategy to Use?

Getting your bidding strategy right can make a significant difference to your results and efficiency. Request a free SwiftLead audit and we'll review your current setup, analyse your conversion data, and recommend the bidding approach best suited to your account's maturity and goals.

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