How much does Google Ads cost per month?

There is no fixed budget for Google Ads. A local SME can start with 300 to 600 pounds per month, a growing e-commerce business will invest between 1,000 and 3,000 pounds, and a large enterprise may spend over 10,000 pounds per month. The ideal budget is calculated from your target CPA and conversion rate.

What is the average CPC on Google Ads?

The average CPC across all industries is around 2.41 pounds on the Search Network. But it varies enormously by sector: from 0.10 pounds in low-competition niches to over 50 pounds in legal or finance.

What is ROAS in Google Ads?

ROAS (Return On Ad Spend) measures the revenue generated for every pound invested in advertising. Formula: ROAS = Revenue generated divided by ad spend. A ROAS of 4 means you generate 4 pounds in revenue for every pound invested. A ROAS of 4 to 8 is generally considered good in e-commerce.

What is the minimum budget to run Google Ads?

Below 300 pounds per month, Google Ads becomes very difficult to optimise. The algorithm lacks data and Smart Bidding strategies cannot calibrate. A budget of 500 pounds concentrated on a few precise keywords is better than 200 pounds spread across many keywords.

How much does Google Ads really cost? Budget, CPC and ROAS explained

Joao Vangeneberg
Jun 17
5 min read

It's the question every advertiser asks before getting started and often after burning their first budget without understanding why. How much do you need to invest in Google Ads to get results? What is the average cost per click? And how do you know if a campaign is truly profitable?

The truth is there's no universal answer. The cost of Google Ads depends on your industry, your objective, the quality of your account and your ability to track the right metrics. This guide demystifies cost mechanics and gives you the concrete benchmarks to build a profitable Google Ads budget.

Golden scale balancing coins and violet light on a dark background — Google Ads investment and return on ad spend — Every pound invested in Google Ads must weigh its worth in return. Understanding CPC, CPA and ROAS means learning how to read that balance.

📌 Recommended prerequisites

Before reading this article, get familiar with the Google Ads auction system, the 6 campaign types and the 7 mistakes burning your budget.

0,10€

Minimum CPC possible in low-competition sectors

50€+

CPC observed on ultra-competitive legal or financial keywords

2,69€

Average CPC across all industries on the Search Network (WordStream, 2024)

What Google Ads really costs the components of your budget

A Google Ads budget isn't a fixed cost. It's a performance-based system where you only pay when someone clicks on your ad. But that cost per click (CPC) varies considerably depending on three main factors.

Auction gavel striking on a dark surface with CPC text — Google Ads cost per click varies with competition in your industry — CPC on Google Ads works like a real-time auction. The more competition in your sector, the higher the price per click climbs.

1. Your industry

This is the most determining factor. A business lawyer will pay between £20 and £50 per click on keywords like "commercial contract solicitor". An e-commerce store selling fashion accessories will pay between £0.30 and £1.50 for "leather handbag". Competition between advertisers in your sector sets the price floor.

Sector	Estimated average CPC (EU)	Competition level
Legal / Finance	15€ – 50€	🔴 Very high
Insurance	8€ – 25€	🔴 Very high
Real estate	3€ – 12€	🟠 High
B2B SaaS / Software	4€ – 15€	🟠 High
E-commerce fashion/home	0,30€ – 2€	🟡 Medium
Restaurants / Local	0,50€ – 3€	🟡 Medium
Online education	1€ – 5€	🟡 Medium

2. Quality Score

As explained in our article on the 7 mistakes burning your budget, a high Quality Score reduces your actual CPC. Two advertisers can bid on the same keyword and pay very different prices depending on the quality of their ads and landing pages.

3. Timing and seasonality

CPCs increase during high-demand periods: Black Friday, Christmas, back-to-school, Valentine's Day. Anticipating these budget spikes is essential to avoid being outbid at the moment when your audience is most ready to buy.

CPC, CPM, CPA : untangling Google Ads metrics

Before setting your budget, you need to understand the three fundamental cost metrics in Google Ads.

Metric	Definition	When to use
CPC (Cost per click)	What you pay each time a user clicks on your ad	Search, Shopping campaigns
CPM (Cost per 1,000 impressions)	What you pay for 1,000 ad displays, whether clicked or not	Display, YouTube (awareness)
CPA (Cost per acquisition)	What each conversion costs you on average (sale, lead, call…)	Performance-focused campaigns

💡 The metric that really matters

CPC is just an intermediate cost. What matters for profitability is CPA. How much each acquired customer costs and ROAS; how much your ad spend generates in return. A high CPC can be perfectly profitable if your conversion rate is excellent.

ROAS : the Google Ads profitability metric to master

ROAS (Return On Ad Spend) measures the revenue generated for every pound invested in advertising. It's the central metric for managing the profitability of a Google Ads campaign.

Formula: ROAS = Revenue generated ÷ Ad spend

✅ Concrete example

You spend £1,000 on Google Ads and generate £4,500 in revenue. Your ROAS is 4.5 — meaning £4.50 generated for every £1 invested. A ROAS of 4 to 8 is generally considered good in e-commerce, depending on margins.

Target ROAS vs actual ROAS : Don't confuse them

Target ROAS is what you set as a goal in your bidding strategy. Actual ROAS is what your campaigns genuinely produce. If your target ROAS is 5 but your actual ROAS is 2, your campaign is destroying value — even if sales are increasing.

⚠️ Beware of misleading ROAS

A high ROAS doesn't necessarily mean a profitable campaign. If your net margin is 20% and your ROAS is 3, you're losing money. ROAS must always be viewed alongside your actual margins to assess true profitability.

Hand using a mechanical calculator on a dark desk with ROAS text — calculating Google Ads budget from target CPA and ROAS — A good Google Ads budget isn't guesswork. It's calculated: target CPA × conversion rate × required click volume.

Quel budget Google Ads prévoir selon votre situation ?

La question du budget minimum est l'une des plus fréquentes. La réponse dépend de votre objectif, de votre secteur et de la stratégie d'enchères choisie.

Profile	Recommended monthly budget	Realistic objective
Local SME, beginner	300€ – 600€/month	Local visibility, first leads
E-commerce beginner	500€ – 1 000€/month	Testing Shopping campaigns
Growing SME	1 000€ – 3 000€/month	Regular leads, positive ROAS
Scaling e-commerce	3 000€ – 10 000€/month	Target ROAS, automation
Enterprise / B2B	10 000€+/month	SERP dominance, Performance Max

🔴 Absolute minimum budget

Below £300/month, Google Ads becomes very difficult to optimise properly. The algorithm lacks data, Smart Bidding strategies can't calibrate, and you risk paying a lot for very little. Better a £500 budget concentrated on 3 precise keywords than a £200 budget spread across 50.

How to calculate your Google Ads budget : the objective-first method

Rather than starting from an arbitrary budget, build yours from your conversion objective.

Define your target CPA — how much can you afford to pay to acquire one customer?
Estimate your conversion rate — on average, 2 to 5% of visitors convert on an optimised landing page
Calculate your maximum sustainable CPC — target CPA × conversion rate = max CPC
Estimate the click volume needed — desired conversions ÷ conversion rate
Deduce your monthly budget — click volume × estimated CPC in your sector

✅ Calculation example

Target CPA: £50 · Estimated conversion rate: 3% · Max sustainable CPC: £50 × 3% = £1.50 · Goal: 20 leads/month · Clicks needed: 20 ÷ 3% = 667 clicks · Estimated monthly budget: 667 × £1.50 = £1,000/month