What Is Ad Copy?
Ad copy refers to the written content within a paid advertisement. In the context of Google Ads search campaigns, ad copy consists of the text visible to a user on the Google search results page: the headline, the display URL, and the description lines. These three elements together form the ad unit that competes for attention in a results page where multiple advertisers may appear simultaneously.
In the modern Google Ads interface, the standard ad format is the Responsive Search Ad (RSA). An RSA allows you to provide up to 15 distinct headlines (each a maximum of 30 characters) and up to 4 descriptions (each a maximum of 90 characters). When a search occurs, Google selects and combines three headlines and two descriptions to assemble the ad. Over time, through repeated testing across many auctions, the system learns which combinations produce the strongest performance and increases their share of impressions. This is different from the older Expanded Text Ad format, where you wrote fixed combinations, and what you wrote was exactly what appeared.
Effective ad copy accomplishes several things at once. It must signal relevance to the user's search query, meaning the user recognises that your ad addresses their need. It must convey enough about your offer to attract the right clicks while deterring irrelevant ones, a consideration that directly affects your advertising costs. It must communicate a reason to choose you over competitors appearing in the same results. And it must do all of this within character limits that allow for only a sentence or phrase at a time.
Ad copy quality influences your Quality Score, which is one of the three components Google uses to determine your Ad Rank (alongside your bid and the expected impact of ad extensions). A higher Ad Rank means your ad appears in a better position on the page, and it means you often pay less per click than a competitor with a lower score bidding the same amount. Investing time in writing high-quality, relevant ad copy therefore has direct cost implications for every rand you spend.
Ad Copy In Practice
The two scenarios below are illustrative examples, not Juicy Designs client results. The figures indicate the scale of effect that ad copy work typically produces, so treat them as indicative rather than measured.
Picture a Cape Town estate agency running Google Ads targeting buyers searching for property in the Southern Suburbs. Its existing ad copy uses generic phrases that could apply to any agency: "Find Your Dream Home", "Cape Town Property Experts", "Search Listings Now". Clicks are coming through but the conversion rate (enquiries per click) sits below 2%, and the cost per lead has climbed to over R800.
A rewrite focused on specificity and differentiation might produce headline variations such as: "Cape Town Southern Suburbs Agents", "Sold 47 Homes in Claremont in 2024", "No Sole Mandate Required", "Free Property Valuation Today", "10-Day Average Time To Offer", and "Rated 4.9 Stars by 180 Clients". Description lines would address the main concern of the target audience: "We work exclusively in the Southern Suburbs and have deeper market knowledge than any generalist agency. Call us for an honest, no-obligation property valuation."
The new copy is more relevant to the specific suburb searches that trigger the ads, includes social proof and specific claims that distinguish the agency from competitors, and addresses the common hesitation about sole mandates. Over something like six weeks, a rewrite of this kind could plausibly lift click-through rate from around 3.5% to around 6%, and push the conversion rate to around 4%. Cost per lead might drop from over R800 to something in the region of R450, on the same monthly budget of R12,000, without any change to bids or keyword match types.
This example illustrates a principle that applies across industries in South Africa: generic ad copy wastes budget, while specific, differentiated copy improves every downstream metric. In markets where Google Ads costs per click are elevated (R50 to R200 for competitive service categories in Johannesburg and Cape Town), the influence that ad copy quality has on campaign efficiency is substantial.
One additional consideration for South African advertisers is the importance of including a clear price signal or qualifying statement where relevant. Imagine a Pretoria medical practice advertising specialist consultations that adds "Private Consultations from R900" to a headline. This single addition would typically reduce clicks from patients seeking government hospital referrals, while pre-qualifying those who do click as already aware of and accepting of the fee structure. Fewer but better-qualified clicks at the same average CPC produces a more efficient campaign even before any other optimisation.
FAQ
How many headlines and descriptions should I write for a responsive search ad?
Google recommends providing all 15 headlines and all 4 descriptions to give the machine learning system maximum material to test. Ads with fewer than 10 headlines receive a lower Ad Strength score. Write each headline to stand alone as a meaningful phrase, because Google will combine them in different positions and you cannot predict which three will appear together on any given auction.
What is a good Ad Strength for a responsive search ad?
Google rates ad strength as Poor, Average, Good, or Excellent. Aim for Good or Excellent. The most common reasons for a lower rating are duplicate or very similar headlines, headlines that are too generic, and failing to include the keyword theme in at least one headline. Improving Ad Strength from Poor to Excellent has been associated with up to 9% more clicks in Google's own studies, which is material when South African CPCs are already elevated.