Solved: Setting up Conversion Tracking for Google Hotel Ads

Hi there,

Thanks for reaching out! Happy to give you some initial thoughts and guidance on the conversion tracking issue you're having with Google Hotel Ads and Resnexus. It's a really common problem when you've got an external booking platform in the mix, so you're definitely not alone. Getting this right is probably the single most important thing for your campaigns, as without accurate data, Google's pretty much flying blind.

I've had a good look at what you've described, and I'll walk you through how I'd approach this. It can get a bit techy, but I'll try to keep it as straightforward as possible.

First off, let's look at why your current setup isn't working as it should...

You've mentioned that you're importing GA4 conversions into Google Ads, but Google Ads is only picking up a fraction of them. This is a classic symptom of a disconnect in how the two platforms attribute conversions. GA4 uses its own model (usually data-driven) and looks at all traffic sources, while Google Ads is laser-focused on its own clicks. They often disagree, especially when a user journey involves multiple touchpoints.

The bigger issue, though, is that you're sending a delayed and incomplete signal to the Google Ads algorithm. For an automated bidding strategy like Maximise Conversions to work properly, it needs immediate, accurate feedback. It needs to know, "this specific click, from this user, on this keyword, at this time of day, resulted in a booking of this value". When you feed it incomplete data from GA4, it can't make smart decisions, which usually means you end up with higher costs and fewer bookings. You're basically asking it to optimise with one hand tied behind its back. It's not a reliable way to scale things up.

The goal is to get a direct line of communication from the point of sale (your Resnexus confirmation page) straight back to Google Ads. This bypasses GA4's view of the world and gives Google Ads the pure, unfiltered data it craves.

We'll need to look at your booking platform, Resnexus...

Everything hinges on what Resnexus allows you to do. When a user clicks your ad, they land on your website. Then, when they go to book, they're sent over to Resnexus's domain. This is a cross-domain journey, and it's where standard tracking often breaks. After they complete the booking on Resnexus, they're hopefully sent back to a "thank you" or confirmation page on your own website. This is the critical moment where we need to capture the conversion data.

So, the very first thing to do is some digging into Resnexus's support documentation. This is your path of least resistance. Most modern booking platforms have dealt with this issue hundreds of times and often have a built-in solution. You should search thier help centre for terms like:

• -> "Google Ads conversion tracking"
• -> "Google Tag Manager integration"
• -> "Confirmation page redirect"
• -> "Adding custom scripts to confirmation page"

What you're looking for is an official, supported method. They might have a simple field where you can just paste your Google Ads conversion tag ID and label. If they do, that's your golden ticket. It's the most stable and reliable way to do it, because they'll be responsible for making sure it keeps working. If you find instructions, follow them to the letter. This would be the best possible outcome.

I'd say you need to get technical if there's no easy option...

If you search their docs and come up empty, then we have to roll up our sleeves and build the connection ourselves using Google Tag Manager (GTM). You're already using GTM, which is great – it gives us the tools we need. The plan is to make the Resnexus confirmation page "talk" to GTM when a booking happens.

The best way for it to talk is through something called the Data Layer.

Think of the Data Layer as a hidden message board on your website. When something important happens, like a confirmed booking, the booking platform can push a little message onto this board. The message might say, "event: 'purchase', transaction_id: '12345', value: '450.00', currency: 'USD'". Google Tag Manager is constantly listening to this message board. When it sees that specific 'purchase' message, it can then fire your Google Ads conversion tag and send all that lovely, accurate data straight to your ad account.

Your mission, should you choose to accept it, is to find out if Resnexus pushes this kind of data to the Data Layer on its confirmation page. You can do this yourself without being a developer:

1. Make a test booking (or go through the process right up to the final confirmation).
2. On the final "Thank You" or confirmation page, right-click anywhere and select "Inspect" or "Inspect Element". This will open up the browser's developer tools.
3. In the developer tools, click on the "Console" tab.
4. Type dataLayer into the console and press Enter.

You'll see an array of objects. Look through them for anything that looks like purchase information. You're hunting for variables like transactionId, transactionTotal, revenue, value, and currency. If you see them, fantastic! That means Resnexus is already providing the data we need. We just have to tell GTM how to read it.

If you find this data, the next steps in GTM would be:

• -> Create Data Layer Variables: For each piece of data (like transaction ID and value), you'd create a "Data Layer Variable" in GTM to capture it.
• -> Create a Custom Event Trigger: You'd create a trigger in GTM that fires only when it sees the specific event name for a purchase (e.g., 'purchase', 'booking_confirmed', or whatever Resnexus calls it).
• -> Configure Your Google Ads Tag: You would then take your existing Google Ads Conversion Tracking tag in GTM and tell it to fire on that new Custom Event Trigger. You'd also feed it the dynamic values for conversion value and transaction ID using the Data Layer Variables you just created.

This setup ensures you're not just counting conversions, but you're also reporting the actual revenue from each booking. This is incredibly powerful because it lets you optimise for Return On Ad Spend (ROAS), not just a flat cost per booking. For a hotel, where booking values can vary massively, this is the way to go.

You probably should check for other tracking methods...

What if you check the Data Layer and there's nothing there? It's a bit of a pain, but we're not out of options yet. The next thing to look at is the URL of the confirmation page itself. Does Resnexus pass the booking information in the URL?

Sometimes, a booking platform will send you to a URL that looks somthing like this:
www.yourhotel.com/thank-you?booking_id=12345&booking_value=450.00

If it does, you can use GTM to "scrape" these values from the URL. You'd use a "URL Variable" in GTM to pull out the booking_id and booking_value, and then use those to populate your Google Ads tag. It's a bit more fragile than the Data Layer method (if they change their URL structure, your tracking breaks), but it's a perfectly valid plan B.

If neither the Data Layer nor the URL contains the data, your final, most robust but also most complex option is to look at a server-to-server integration using an API. This almost always requires a developer. In this scenario, when a booking is made, the Resnexus server sends a secure, direct message to Google's server with the conversion data. It's the most accurate method of all because it's immune to ad blockers, cookie restrictions, and other browser-related issues. It's the "pro" solution, but it comes with a cost. You'd need to see if Resnexus offers a "conversion API" or "webhooks" that a developer could use to build this connection.

You'll need a solid foundation before you scale...

I know this sounds like a lot of faff just to get a number to show up correctly, but I can't overstate how important this is. The quality of your entire paid advertising effort is built on this foundation. With inaccurate tracking, you might pause a campaign that's actually making you money or scale up a campaign that's secretly losing it.

Think of it like this: right now, your Google Ads account is getting blurry, second-hand reports about what's working. By implementing direct conversion tracking, you're giving it crystal-clear, 20/20 vision. The algorithm will be able to see exactly which ads and keywords are driving high-value bokings and will automatically bid more aggressively to get more of them. This is how you move from just "getting some bookings" to building a predictable, scalable revenue engine for your hotel.

I remember working on a campaign for a client in the student recruitment space, which had a similar issue with a third-party application portal. They were struggling with a high cost per booking. After we spent the time to properly implement direct conversion tracking via GTM, their cost per booking dropped by 80% within two months. It wasn't because we wrote amazing new ads; it was simply because the algorithm finally had the right data to do its job properly. It could tell the difference between a low-value enquiry and a high-value confirmed booking and put the budget where it mattered.

I've detailed my main recommendations for you in a table below to make it a bit clearer.

Once you have this technical foundation in place, you can then start to properly optimise your Google Hotel Ads. You can trust your Cost per Acquisition (CPA) and ROAS data. You can make confident decisions about budgets, bids, and strategy, knowing that the numbers you're looking at reflect the reality of your business.

This is often the point where working with an expert can make a huge difference. The technical setup can be tricky, and one small mistake in a GTM trigger or variable can mean no data comes through. An agency or consultant who has done this dozens of times can typically diagnose and fix the issue in a few hours, saving you weeks of frustration and wasted ad spend. More importantly, once the tracking is fixed, the real work begins – optimising the campaigns to drive profitable growth. That's a whole other ball game involving campaign structure, bidding strategies, ad copy, and landing page optimisation.

If you'd like to chat through this in more detail, we offer a free, no-obligation initial consultation where we can have a look at your accounts together and map out a clear action plan. It might be helpful to have a second pair of expert eyes on it.

Hope this detailed breakdown helps you get things sorted!

Regards,

Team @ Lukas Holschuh