Online advertising campaigns: channels, costs and how to start

An online advertising campaign is a paid activity on Google, social platforms or other networks, designed to bring specific people to a specific action (an enquiry, a purchase, a sign-up) and measurable down to the last euro. The right channel depends on one question: is your customer already searching for what you sell? If so, start with Google Ads. If not, or if you sell to well-defined professional profiles, look at Meta Ads or LinkedIn Ads.

The platform is usually not the problem. Campaigns that do not pay back fail for three recurring reasons: a vague objective, incomplete tracking and no optimisation after launch. This guide explains how to choose the channel, what campaigns cost, how to set them up step by step and when it is better not to run them yet.

How to choose the channel: existing demand or demand to create

Google Ads intercepts demand that already exists. Someone searching for "communication agency Milan" or "HR management software" is looking for a supplier: a relevant ad at that moment converts better than any other channel. Search campaigns show text ads among the results, Display and YouTube work on awareness, and Performance Max spreads the budget across all Google channels with the help of artificial intelligence. For beginners, Search on a few high-intent commercial keywords is the starting point with the best balance of risk and result.

Meta Ads (Facebook and Instagram) works the other way round: it creates demand by reaching people who resemble your customer even if they are not searching for anything at that moment. Its strength is depth of targeting (age, area, interests, behaviours, audiences similar to existing customers). It works well for consumer products and services, for remarketing to people who have already visited the site and for building awareness with strong creatives.

LinkedIn Ads is the channel for high-ticket B2B. It lets you reach people by role, industry, company size and seniority. The cost per click is on average higher than on Google and Meta, but for those selling high-value contracts the quality of the leads often justifies it. The most used formats are sponsored content in the feed, document ads and direct messages.

TikTok, YouTube and programmatic (automated buying of space across site networks) also exist, but for an SME starting from zero they are second-tier channels: you open them when one of the three above works and there is budget to test more. How these channels fit into the overall plan is covered in the guide to digital marketing for SMEs.

How much an online advertising campaign costs

There is no fixed price: you decide the budget and the cost of each click is set by an auction. The most cited industry estimates for Italy put the cost per click on Google's search network between roughly 0.30 and 2.50 euros, with peaks above 10 euros in the most contested sectors such as finance, insurance and legal services. These are orders of magnitude, not promises: the real cost depends on keywords, the quality of the ad and landing page, competition and location.

For an SME starting with Google Ads and Meta Ads, an advertising investment of 1,500-3,000 euros a month is a reasonable starting point to collect useful data. Below 500 euros a month per channel the numbers are too small to learn what works. On top of that comes the cost of whoever manages the campaigns: a freelancer on a single channel stays under 1,000 euros a month, an agency between 300 and 6,000 depending on scope. The bands and what they include are explained in the guide on how much outsourcing marketing costs and in the one on the cost of a communication agency.

Cost per click alone says little. What matters is the cost per useful lead and, further down, the cost per acquired customer compared with what that customer is worth. A 5-euro click that brings a 20,000-euro contract is an excellent deal; a 0.30-euro click that does not convert is money lost.

How to set up a campaign in six steps

1. Objective. Awareness, leads or sales: each objective calls for different formats, messages and metrics. A campaign with two objectives at once reaches neither. 2. Tracking. Verified Meta pixel, configured Google Ads conversions, active Google Analytics 4, consistent UTMs on every link. Without this step you optimise in the dark. 3. Creatives. At least two or three message and image variants to compare: it is the only way to find out what really works.

4. Test. Start with a trial budget and a narrow audience, giving the platform time to collect data before judging. 5. Optimisation. Every week, remove keywords and audiences that do not pay, move budget to what converts, replace creatives that are wearing out. This is the phase that separates a mediocre campaign from one that generates return systematically. 6. Scale. Only when the cost per lead is stable do you raise the budget, in steps, not by doubling overnight.

The metrics to watch at each stage (CPA, conversion rate, ROAS, return on budget) are in the guide to marketing KPIs and metrics.

Tracking: why you cannot optimise without data

In 2026 measuring conversions is harder than before: third-party cookies increasingly limited, mandatory privacy consent, platforms that see only part of the journey. Whoever has not implemented tracking properly spends budget without knowing what is converting, and the platforms' automated campaigns learn from wrong data. Before putting significant budget into advertising, check that every enquiry reaches analytics with its source. It is the investment with the highest return you can make before any campaign.

When not to run campaigns (yet)

There are situations where advertising burns budget. When the website does not convert: every euro of traffic is wasted until the landing page is clear and the form is short. When there is no defined offer: advertising amplifies a message, it does not invent one. When the margin cannot carry the acquisition cost: if a customer leaves you 300 euros and you spend 400 to acquire them, more campaigns mean more losses. When nobody in the company reads the numbers and turns them into decisions. In these cases the first investment goes into the website, the offer or measurement, not the advertising budget.

The most common mistakes

Opening Google, Meta and LinkedIn together with a budget that supports only one. Judging a campaign after three days, while the platform is still learning. Sending every click to the homepage instead of a page built for that ad. Measuring clicks instead of leads. Leaving automated campaigns unattended: Performance Max and similar formats optimise for the goal you give them, even when it is the wrong one. Not excluding irrelevant terms with negative keywords, paying for clicks that cannot become customers.

Who should manage the campaigns

There are four options: an in-house person, a freelancer per channel, an agency, an external team built around the objective. An in-house person makes sense when the workload really fills a position. A freelancer is the leanest choice for a single channel. An agency brings method and coverage, with less control over individual professionals. The criteria for choosing are in the guide on agency or freelancer. Whatever the model, someone has to set priorities and read the results: if nobody in the company can, an external marketing manager can do that job at a variable cost.

Frequently asked questions about online advertising campaigns

How do you advertise online? You choose a platform based on where the customer is (Google if they search, Meta if they have to be reached, LinkedIn for B2B), define an objective, set up tracking, launch with a trial budget and optimise on the data. The minimum useful budget to learn anything is a few hundred euros a month per channel.

How much does a Google Ads campaign cost? You decide the budget. The cost per click on the search network in Italy averages between roughly 0.30 and 2.50 euros, much more in contested sectors. For an SME, 1,500-3,000 euros a month of advertising investment is a sensible starting point, plus the cost of whoever manages the campaigns.

What is the difference between Google Ads and Meta Ads? Google intercepts people already searching for a product or service; Meta reaches people with the characteristics of the ideal customer, even if they are not searching. They are often used together: Google captures those ready to buy, Meta brings back to the site those who did not convert straight away.

What types of Google Ads campaigns are there? Search (text ads in the results), Display (banners across the site network), Shopping (product listings for e-commerce), YouTube (video) and Performance Max (which combines all channels automatically). Beginners should start with Search.

How long does it take to see results? The first data arrives within days, but it usually takes four to eight weeks of testing and optimisation to get a stable campaign. Judging earlier is the fastest way to throw the budget away.

In short

An online advertising campaign works when it has a clear objective, a channel that fits where the customer is, reliable tracking and someone who optimises it every week. Start with one channel, with a proportionate budget, and increase only when the numbers hold.

If you need a media buyer or a team of specialists on the right channel, without hiring and without an agency's structure, see how Really Hub works or the marketing services you can activate.