Asking ‘How much do Google Ads cost?’ is like asking ‘How much does a house cost?’ It depends where you buy, what you’re building, and what you’re trying to achieve. For lead gen, the better question is: ‘How much can I afford to pay for a real enquiry?’
Budget is always the first question. It’s rarely the right first question — but it’s the one every business owner asks, and it deserves a straight answer.
So let’s answer it properly.
What Actually Drives Google Ads Costs (It’s Not Just ‘Competition’)
Google Ads operates on an auction system. Every time someone searches, an auction happens in milliseconds. Your cost is determined by:
Quality Score — Google’s rating of how relevant your ad and landing page are to the search. Higher Quality Score = lower cost per click.
Bid Amount — The maximum you’re willing to pay per click. Higher bids generally mean more impressions.
Expected Click-Through Rate — How likely your ad is to be clicked based on historical data.
Ad Relevance — How closely your ad matches the searcher’s intent.
Competition — How many other businesses are bidding on the same keywords.
A well-structured account with high Quality Scores can outperform a bigger budget with poor structure. This is why the same $3,000/month produces dramatically different results in different hands.
Setting A Realistic Test Budget For 30, 60 And 90 Days
The 30-Day Minimum:
Google’s algorithm needs data. The Smart Bidding strategies that drive lead gen performance require approximately 30–50 conversions per month to optimise effectively. Your 30-day budget should be set to give you a realistic shot at hitting that threshold.
If your industry cost per lead is $100, you need $3,000–$5,000 in month one to generate meaningful data.
Days 30–60: Optimisation Phase
Now you have real data. You know which keywords convert, which ads resonate, and what your actual CPL is. This is when your agency should be aggressively pruning waste and scaling what works.
Days 60–90: Performance Phase
By day 90, you should have a stable CPL, a clear view of your best-performing campaigns, and a data-backed decision about whether to increase, hold, or adjust budget.
Don’t increase budget before optimising. Adding money to a broken campaign is the most common — and most expensive — mistake in Google Ads.
CPL, CPA, ROAS: The Only Numbers That Matter For Lead Gen
Cost Per Lead (CPL) — Total spend ÷ number of enquiries. The primary KPI for service businesses.
Cost Per Acquisition (CPA) — Total spend ÷ number of new customers. Requires CRM data to track post-lead outcomes. More meaningful than CPL alone.
Return On Ad Spend (ROAS) — Revenue generated ÷ ad spend. Most relevant for eCommerce; for service businesses, use CPA instead.
Know your numbers before you start. If your average client is worth $5,000 and you close 30% of leads, you can afford a CPL of up to $1,500 and still be profitable. If you don’t know these numbers, you’ll never know if your campaigns are working.
How Different Industries And Locations Change Your Cost
Average CPCs (cost per click) in Australia vary widely:
- Trades (plumbing, electrical, HVAC): $3–$12 per click
- Legal and financial services: $15–$45 per click
- Dental and medical: $5–$20 per click
- Real estate: $4–$15 per click
- Home building and renovation: $4–$10 per click
Location matters too. Competitive metro markets like Sydney CBD cost more than regional centres. A Brisbane home builder targeting outer suburbs can achieve lower CPCs than the same business targeting the inner city.
Industry + location + competition = your real cost. Generic ‘averages’ are a starting point, not a budget.
When To Increase Budget — And When To Pause
Increase budget when:
- Your CPL is at or below your target and you’re not capturing full demand (low impression share)
- You have more capacity to handle leads than you’re currently receiving
- Your account has been optimised and you have at least 60 days of clean data
Pause or reduce when:
- Your CPL is significantly above target with no clear path to improvement
- Your business capacity is full — paying for leads you can’t service is waste
- There’s a seasonal dip in demand for your service
Budget decisions should be data-driven, not emotional. ‘It feels like it’s not working’ is not a metric. CPL trend over 90 days is.
Frequently Asked Questions
Q: Is there a minimum budget for Google Ads to work?
For most service businesses in Australian capital cities, $1,500–$2,000/month in ad spend is the practical minimum. Below this, you often can’t generate enough click volume and conversion data for the algorithm to optimise, and your results will be inconsistent.
Q: Should I increase my budget if my campaigns aren’t working?
Generally, no. More budget amplifies what’s already happening — if your campaigns are underperforming, adding money makes the problem bigger, not smaller. Fix the structure, copy, and landing page first, then scale.
Q: What percentage of my budget should go to the agency vs. ad spend?
A reasonable split for SMBs is 70–80% ad spend, 20–30% management fee. If your agency’s fee is consuming more than 30% of your total budget, the ratio is working against you — you don’t have enough ad spend to generate meaningful data.
Q: How do I know if I’m overpaying per click?
Check the Google Ads Keyword Planner for estimated CPCs in your industry and location. If your actual CPCs are significantly higher, it could indicate a low Quality Score — which often points to poor ad relevance or landing page experience.
Q: Can I run Google Ads with $500/month?
In low-competition markets or very niche industries, yes — results are possible. In metro Australian markets for competitive services, $500/month will likely generate too little data and too few clicks to see meaningful results. It’s not impossible, but it’s an uphill battle.
