The most common problem in Google Ads accounts has less to do with the campaigns themselves than with measurement. The account reports clicks and impressions in full, yet nobody knows which campaign or keyword actually brings in customers. Budget decisions are then based on guesswork, and Google's automated bidding strategies work from the wrong signals.
In this guide we explain how to measure the three most important enquiry channels for service businesses in particular (phone, WhatsApp and the contact form) in Google Ads, and the mistakes most often made during set-up.
What is a conversion, and what should we measure?
A conversion is a valuable action that a visitor from an ad takes for your business. For service businesses this usually means making an enquiry. Metrics such as time on page or pages per visit are useful indicators, but should not be used as primary conversions; otherwise Google optimises to find visitors who never enquire.
- Primary conversions: phone calls, WhatsApp messages, form submissions, quote requests
- Secondary (observation-only) conversions: viewing the pricing page, downloading a brochure, clicking for map directions
Measuring phone calls
Phone enquiries arrive by two different routes, and each should be measured separately:
- The call asset in the ad: the user taps the phone number in the ad directly. These calls are measured with Google Ads call conversions, optionally counting only calls longer than a set duration.
- The phone link on the website: the user visits the site and taps the number on the page. This click is measured with a conversion tag attached to the tel: link.
A click on the site does not guarantee that a call was actually made; it only shows the intent to call. If more precise measurement is needed, Google forwarding numbers on the website or a call tracking service can be used.
Measuring WhatsApp enquiries
For local service businesses in particular, enquiries via WhatsApp can overtake phone calls. Clicks on the WhatsApp button or wa.me link on the site should be defined as a separate conversion. Tying them to the same conversion as phone calls prevents you from seeing which channel people prefer.
Adding a pre-filled message (for example "I'm getting in touch from your website") also helps you tell whether incoming messages came from the ads or from another channel.
Measuring form submissions
For forms, the most reliable method is to trigger the conversion when the form has been submitted successfully: either via a redirect to a thank-you page or an event that fires at the moment submission succeeds. Counting clicks on the submit button as conversions is a mistake; incomplete or invalid forms will also appear as conversions.
Cookie consent, data protection and Consent Mode
Google Ads conversion tags use cookies. Data protection obligations, such as those under KVKK (Türkiye's data protection law) and GDPR, therefore require visitor consent and an up-to-date cookie policy. Google's Consent Mode passes the visitor's consent status to the tags; when consent is not given, the tags send limited signals without cookies and Google fills the gaps with modelling.
Measurement set up without a consent framework carries legal risk and causes sudden drops in data when a consent mechanism is added later. That is why cookie consent should be planned at the same time as measurement.
Common set-up mistakes
- The same conversion being counted twice, via both the Google Ads tag and an Analytics import
- Light actions such as page views being marked as primary conversions
- Phone, WhatsApp and forms being lumped into a single conversion
- The form conversion firing on a click of the submit button
- Tags disappearing after a site redesign without anyone noticing
- Test conversions and internal clicks polluting the reports
How to verify your set-up
- Complete each conversion action on your site yourself once.
- Use Google Tag Assistant to check that the tag fires at the right moment.
- Confirm that the status shows as "Active" on the conversion actions screen in Google Ads.
- In the first few weeks, compare the number of enquiries attributed to ads with the calls, messages and forms you actually received.
Conclusion
Correctly configured conversion tracking is a prerequisite for managing a Google Ads budget with data rather than guesswork. Measuring phone, WhatsApp and forms separately, planning cookie consent from the start and verifying the set-up regularly lets you see clearly which spend brings in customers.
If you would like us to check the measurement set-up of your existing Google Ads account, get in touch; in a free account review we will look together at whether your conversion tracking is working correctly.