The Google Vehicle Ads Metrics That Actually Matter for UK Car Dealers
If you focus on the wrong metrics, you will soon run out of budget and fail to get the results you want. We see this time and time again as Google Vehicle Ads specialists.
Google Vehicle Ads (GVA) provides you with a lot of data to review. But not all of it tells you whether the campaign's actually making you money, and some of it can even be misleading if you don't know what you're looking at.
At WeAdvertiseAnyCar, we've pulled together the metrics that genuinely matter, the ones that tell you if your GVA campaign is working, and the ones that tell you where it's quietly losing you money.
Cost Per Click vs. Cost Per Lead
Most dealers we talk to will use cost-per-click and cost-per-lead interchangeably, but the two terms have very separate definitions.
Cost per click is how much you’re spending on each person who clicks your ad, while cost per lead is how much you’re spending for each person sending you an enquiry related to your ad.
Most dealers will see a low cost per click (CPC) as a win, but a cheap click that goes nowhere costs you more than an expensive click that turns into an enquiry. For example, if you're paying £2 per click and none of those visitors are filling in a form, calling the dealership, or booking a test drive, your CPC doesn't actually tell you anything about your campaign's success.
Cost per lead (CPL) is the number you need to watch as it tells you how much you're actually spending to generate a genuine enquiry, not just a visit to the page.
Once you know your CPL, you can start working backwards: how many leads does it take to generate a sale? What's each sale worth? That's where the real picture emerges.
Track the Vehicle Detail Page Engagement
Once the click comes through and they’re on your vehicle detail page, you still need to be tracking metrics.
The signals worth tracking are: time spent on the page, how far they scrolled, whether they viewed the photo gallery, and whether they visited more than one VDP in the same session. Multiple VDP visits in a single session are particularly strong, as they usually mean someone is seriously comparing your stock.
Low time on page combined with high bounce rates is a warning sign. Either the page isn't matching what the ad promised, or the page experience isn't good enough to hold their attention. If you spot this issue, there are some easy fixes you can implement, but you won’t be able to fix anything without tracking these metrics.
You also want to ensure that your user takes an action, such as filling out a form, clicking a click-to-call button, reserving the car, or booking a test drive.
A click-to-call is the highest-intent action of the lot, and industry data show that approximately 67% of automotive conversions come from phone calls.
Tie all of this together with your VDP-to-enquiry conversion rate, which is the percentage of GVA visitors who take any of these actions, and you've got a clear view of whether your pages are doing their job.
If you're driving plenty of clicks but the conversion rate is low, the problem isn't the campaign but your VDP. Slow page load times, weak imagery, unclear pricing, or an enquiry form buried too far down are all factors that undermine a conversion.
Make sure you track your VDP visits and events coming from GVA separately so you can attribute each lead to the ad.
Offline and Showroom Conversions
If you want to truly measure your GVA campaign success, you need to be linking offline conversion back to your campaign, and this is where many dealers go wrong.
A car sale doesn't happen on a website; it’ll most likely happen in the showroom. If you’re not tracking face-to-face transactions, you’ll only have a vague idea of how effective your campaign is in creating a sale. Tracking offline conversions sounds complicated in practice, but it’s fairly straightforward.
Every time someone clicks on one of your GVA ads, Google automatically tags that click with a unique code called a Google Click ID (GCLID). If you have a Google Tracking Tag on your website and your system is set up to capture it, the GCLID is automatically saved in the lead management system you use, along with the customer's details.
Once the user with the GCLID completes a purchase, you can send the sale back to Google Ads as an offline conversion, indicating that the ad resulted in a sale worth £X. Google allows you to import these conversions within a 90-day window, which is enough time to capture deals that take a few weeks to close.
Offline conversion tracking will provide you with accurate, complete data to inform your future decisions about how to use your budget more effectively.
Track Your Cost per Sale
You now know how much it costs you to get a lead, the next thing you want to know, and track is how much a sale actually costs you.
To work that out, you need two things: how many of your leads actually buy (your close rate), and what the average margin on those sales looks like. If you're generating 50 leads a month, closing 10% of them, and spending £2,000 on ads, each sale is costing you £400 in ad spend. Whether that's good or not depends entirely on your margin.
This is also where return on ad spend (ROAS) comes in. ROAS is just the revenue your campaign generates divided by what you spent on it. Spend £2,000, generate £10,000 in vehicle profit, and your ROAS is 5x.
However, ROAS will only mean something if your data is accurate, which is why tracking offline conversions is such a big deal. If offline conversions aren’t accounted for, your ROAS will be a lot lower than it actually is.
Check your Feed Health
When we meet clients who have already set up their GVA, we often see feeds that are not as healthy as previously thought, which often shocks dealers.
Google Vehicle Ads run directly from your inventory feed in Google Merchant Center. Every vehicle in your stock is submitted as a data listing. If that listing has an error, such as a price mismatch between the feed and the VDP, a missing attribute, or an expired image URL, Google disapproves it.
If your ad is disapproved, it won’t show. You want to keep an eye on your disapproval rate as we’ve audited accounts where dealers assumed their full forecourt was being advertised, only to find that a significant proportion of their inventory had been disapproved due to price or mileage mismatches between the feed and their website. The campaign looked fine in Google Ads. The problem was upstream, in Merchant Center, where nobody was checking.
One thing to note is that if persistent price mismatches go unresolved, you risk having your account suspended if the issues aren’t corrected within the timeframe stated in Google’s notification, which is typically 28 days, though some violations carry a shorter window.
Bring your GVA Campaign to the Next Level
There's no shortage of numbers in a GVA campaign, but you want to focus on the numbers that don’t just look pretty but bring you revenue.
The metrics that matter are the ones that follow the buyer's journey all the way to a sale: CPL, VDP engagement, lead actions, page conversion rate, offline attribution, close rate, cost per sale, and ROAS.
At WeAdvertiseAnyCar, reporting on all of these is part of how we manage GVA campaigns for dealers across the UK. If you're not sure what your current campaign is actually delivering, we can audit it and show you exactly where the gaps are. And if GVA sounds all too complicated, we can get you started on Google Vehicle Ads and manage your campaign. We’ve got flexible packages to fit your business’s needs. Get in touch to find out more.