Solved: Scaling Google Ads - Budget and tROAS Adjustments

Hi there,

Thanks for reaching out!

Happy to give you some initial thoughts on your question. It's a common one, and honestly, the advice you see floating around like the "20% rule" is often a massive oversimplification that can actually hold your campaigns back. The real answer, as with most things in paid ads, is a bit more nuanced and depends on what's actually happening in your account.

The short answer is you're right to be cautious, but you're probably being *too* cautious. Let's break down how to think about this properly so you can scale with confidence instead of following some arbitrary rule that someone made up for a blog post.

Let's talk about that '20% rule'...

Right, let's get this one out of the way first. This "rule" is one of those pieces of "best practice" advice that gets repeated so often people assume it's true. Tbh, it's mostly rubbish. It comes from a good place – the idea is to avoid shocking the ad platform's algorithm and resetting the learning phase unnecessarily. Sudden, huge changes *can* cause temporary performance volatility. But treating it as a hard and fast rule is a massive mistake that costs businesses potential revenue.

Think about it logically. You have a campaign that's delivering a fantastic return. Every £1 you put in gives you £8 back. Why on earth would you deliberately limit your growth to a measly 20% a week? You'd be leaving a huge amount of money on the table. In that scenario, the right move is to pour as much fuel on the fire as you can. I've had campaigns where we've doubled or even tripled the budget overnight because the numbers were just that good. Sure, performance might dip for a day or two as the algorithm adjusts to the new spend level, but it almost always stabilises, and you've just fast-forwarded your growth by weeks or months.

The real danger isn't breaking the algorithm. The algorithm is robust; it's designed to spend your money. The real danger is scaling a campaign that isn't actually ready. If your ROAS is just borderline, or if you only have a few conversions, then yes, a massive budget increase is just going to amplify your losses. The 20% rule is a safe training wheel for beginners, but if you want to get serious results, you need to learn to ride the bike properly. The rule should be: if the campaign is highly profitable and stable, scale agressively. If it's not, don't scale at all – fix the underlying problems first.

So, should you change budget and tROAS together?

This gets to the heart of your actual question. The answer depends entirely on the *magnitude* of the changes you're making. The Google/Meta algorithms are incredibly complex learning machines. Every time you make a significant change, you're giving it new information to process. Think of it like teaching a person a new skill. If you try to teach them two completely different things at the same time, they're going to get confused and performance will suffer. But if you make a small adjustment, they can probably handle it.

So, here's how I approach it:

Scenario 1: Aggressive Scaling (e.g., increasing budget by 50%+)

In this case, you should absolutely make the changes seperately. You're making a big adjustment, and you want to isolate the variables to understand the impact and give the algorithm a clean signal. The process should look like this:

1. Increase the Budget: Make your desired budget increase. Don't touch the tROAS.
2. Wait and Observe: Let the campaign run for at least 3-5 days. You're waiting for the daily spend to become consistent and for the CPA/ROAS to find its new level. The "learning" status might reappear in the account, which is perfectly normal.
3. Adjust the tROAS: Once performance has stabilised, you can then adjust your tROAS target based on the new performance level. If your ROAS dropped slightly with the higher budget, you might need to lower your tROAS target to allow the system more breathing room to find conversions at the new scale.
4. Wait and Observe Again: Give it another few days to settle.
5. Repeat the Cycle.

This methodical approach ensures you're not just throwing things at the wall and hoping they stick. You're making calculated moves and giving the system time to adapt. It might feel slower, but it gives you much more control and better long-term results.

Scenario 2: Slow & Steady Scaling (e.g., increasing budget by 10-25%)

If you're just making a small, incremental tweak, it's generally fine to adjust both at the same time. The change isn't significant enough to cause major volatility. The algorithm can likely process both a small budget bump and a minor tROAS adjustment without going haywire. This is the only situation where the "20% rule" has some merit, but even then it's more of a guideline than a strict command.

To make this clearer, I've mapped it out into a simple decision-making process.

You're asking the wrong question...

Here’s the brutally honest truth: if you're worried about whether to change tROAS and budget at the same time, you're likely focusing on a 1% optimisation problem when there might be a 50% improvement opportunity you're completely missing. The best agencies and advertisers don't get amazing results by perfectly timing their budget increases. They get them by building a system that is inherently scalable.

Most campaigns hit a plateau. You find an audience and a creative that works, you increase the budget, and performance is great... until it's not. You keep pushing the budget, but your ROAS starts to tank and your CPA skyrockets. This is completely normal. You've simply saturated the small pocket of your audience that was easiest to convert. The question isn't "How do I push the budget higher?" The question is "How do I make my entire system more efficient so I can afford to acquire customers at a larger scale?"

Scaling isn't a button you press. It's the outcome of improvements in three core areas:

1. Improving Your Ads: Finding new winning audiences and creatives to expand your reach beyond the initial pool of easy converters. There are always more audiences to test.
2. Improving Your Funnel: Increasing the conversion rate of your website or landing page. If you can turn 2% of clicks into customers instead of 1%, you've just doubled the effectiveness of your ad spend without touching the campaign.
3. Increasing Your Customer Lifetime Value (LTV): This is the most overlooked but most powerful lever for scaling. If you can increase the total profit each customer generates over their lifetime, you can afford to pay more to acquire them in the first place. This unlocks more expensive, higher-scale audiences that your competitors can't afford to reach.

If you're stuck, I guarantee the bottleneck is in one of those three areas, not in the timing of your budget increases.

You'll need to understand your numbers: LTV vs. CAC

Let's focus on that last point, because it's the one that separates amateur advertisers from the pros. Most people are obsessed with lowering their Cost Per Lead (CPL) or Cost Per Acquisition (CPA). They're constantly trying to get cheaper clicks and cheaper conversions. This is a losing game. It forces you into a race to the bottom, fighting over the cheapest, lowest-quality audiences.

The real question isn't "How low can my CPA go?" but "How high a CPA can I afford to acquire a truly great customer?" The answer is found by calculating your Lifetime Value (LTV).

The calculation is simpler than it sounds. You just need three numbers:

• Average Revenue Per Account (ARPA): How much revenue does a typical customer bring in per month (or year)?
• Gross Margin %: What is your profit margin on that revenue? (Revenue - Cost of Goods Sold) / Revenue.
• Monthly Churn Rate: What percentage of customers do you lose each month?

The formula is: LTV = (ARPA * Gross Margin %) / Monthly Churn Rate

Let’s run an example. Say you run a SaaS business:

• ARPA = £200/month
• Gross Margin = 85%
• Monthly Churn = 5%

LTV = (£200 * 0.85) / 0.05 = £170 / 0.05 = £3,400

This means that, on average, every new customer you acquire is worth £3,400 in gross margin to your business over their lifetime. This number changes everything. A healthy business model often aims for an LTV to Customer Acquisition Cost (CAC) ratio of at least 3:1. This means for a customer worth £3,400, you can afford to spend up to £1,133 to acquire them and still have a very profitable business.

Suddenly that £150 CPA you were worried about doesn't look so bad, does it? It looks like an absolute bargain. This is the maths that unlocks aggressive, intelligent growth. It frees you from the tyranny of cheap leads and allows you to confidently spend what's necessary to acquire high-value customers.

I've built a simple calculator for you below so you can play with your own numbers and see how this works in practice.

I'd say you need to optimise first, scale second...

Armed with the knowledge of how much you can truly afford to spend, you can now go back and work on the inputs that will allow you to scale. If your campaign isn't performing well enough to scale aggressively, don't just inch the budget up by 20%. Stop increasing the budget altogether and get to work on optimisation. This is where the real gains are made.

1. Relentlessly Test Your Targeting
You've likely found one or two audiences that work. Great. But there are dozens, if not hundreds, more you could be testing. Don't get complacent. You should always have a portion of your budget dedicated to testing new audiences. On Google, this means testing new keyword themes, custom-intent audiences, in-market segments, and remarketing lists. On platforms like Meta, the list is endless: lookalikes of your best customers, different interest stacks, broad targeting once your pixel is mature. We often structure accounts with specific "Testing" campaigns that run on a smaller budget, designed purely to find new, scalable audiences. Once an audience proves itself, we move it into a "Scaling" campaign with a much larger budget. This creates a perpetual motion machine of growth.

2. Make Creative Your Superpower
Audience targeting gets you in the right room, but your ad creative is what starts the conversation. So many advertisers find one ad that works and then run it into the ground for six months. This is a recipe for ad fatigue and plateauing performance. You should be testing new ad copy and new visuals *every single week*. Test different angles, different pain points, different emotional hooks.

For example, if you sell accounting software, don't just talk about features. Test these angles:

• The "Peace of Mind" Angle: "Stop waking up at 3 AM worrying about cash flow. Get clarity and control back."
• The "Growth" Angle: "Your competitors are making data-driven decisions. Are you still guessing? Our dashboards turn numbers into strategy."
• The "Time-Saving" Angle: "Spend less time in spreadsheets and more time growing your business. Automate your invoicing in 5 minutes."

I remember for several of our SaaS clients, we saw massive breakthroughs just from testing UGC-style (User-Generated Content) video ads against their polished studio ads. The lo-fi, authentic feel of UGC often builds more trust and drives conversions at a much lower cost. You never know what will work until you test it.

3. Fix Your Offer and Landing Page
This is the biggest lever you have. Sending expensive traffic to a low-converting landing page is like pouring water into a leaky bucket. Before you spend another pound on ads, be brutally honest about your offer. Is a "Request a Demo" button really the most compelling thing you can offer someone? It’s high-friction and low-value for the prospect. They have to schedule a time, sit through a sales pitch, all for an unknown outcome.

Instead, can you offer a moment of undeniable value for free? A free trial, a freemium plan, a free tool, or a free automated audit. Something that solves a small, real problem for them and makes them *sell themselves* on your full solution. I've seen B2B clients achieve tremendous success by replacing the 'Book a Demo' button with an offer like a free, automated 'Data Health Check' or an SEO audit. This approach can fundamentally change the economics of your ad campaigns and allow you to scale massively.

I've detailed my main recommendations for you below:

To bring this all together, here is the exact advice I would give any client in your position. Forget the generic rules and focus on these core principles of intelligent scaling. This is the framework that allows you to move from cautiously tweaking budgets to confidently building a growth engine.

Ultimately, scaling paid advertising campaigns effectively is a complex skill. It's less about following rigid rules and more about understanding the underlying principles of the system, from algorithmic behaviour to business-level financial metrics like LTV.

While the advice here should give you a much more robust framework to work with, putting it all into practice can be a challenge, especially when you're also trying to run your business. This is where expert help can make a significant difference. An experienced agency can bring years of learnings from hundreds of accounts to the table, helping you avoid common pitfalls, accelerate your testing cycles, and build a truly scalable growth strategy much faster than you could on your own.

We offer a completely free, no-obligation initial consultation where we can take a look at your specific ad account and strategy. We can help you properly calculate your key metrics, identify your biggest opportunities for optimisation, and lay out a clear roadmap for scaling. It's often incredibly helpful for business owners to get a second set of expert eyes on their campaigns.

Feel free to book a call if that sounds useful. Otherwise, I hope this detailed breakdown has been genuinely helpful and gives you the confidence to take control of your campaign scaling.

Regards,

Team @ Lukas Holschuh