Your Google Ads also lift your OTA sales. Here is how to see it.

The conversion tag only watches your website. Your ads do not. They put your tour in front of people who then book wherever they feel safest, and for many travellers that is Viator or GetYourGuide. This guide is about seeing that effect in your own numbers instead of guessing.

In the last guide I showed the common version of the tracking problem. The ad account under-reports. A London operator whose ads I run showed a 0.89x return while the booking system showed 1.88x from direct website sales alone. Once I added the bookings that landed on the OTAs during the same campaigns, the same spend was sitting at roughly 2.4x.

This guide is about the other half of that story. The part of your ad money that turns into OTA bookings, and how to measure it without fooling yourself.

How an ad click becomes an OTA booking

Think about how people actually book a tour. They search, they click your ad, and they look around your site. Then many of them do something the tag cannot follow. They open the app where their account already lives, search your tour name, read the reviews, and book it there.

From where I sit running these accounts, the pattern is easy to recognise. You launch campaigns for a tour, and the OTA sales for that same tour start climbing in the same weeks. Nothing else changed. The ads are the only new thing in the picture.

Here is why the traveller does it.

• Their payment details and booking history already sit in the OTA app
• The OTA listing carries hundreds of reviews, and your website might show none
• They trust the OTA's cancellation policy more than an unfamiliar checkout

None of that is a problem to fix. It is how the market works. The problem is that your ad account gives you no credit for any of it, so you judge the spend on a number that is missing a real part of what it produced.

The tag can be wrong in both directions

The first guide showed the tag under-reporting. It also over-reports, and the OTA effect is usually the reason.

Another operator whose ads I run sells most of their capacity through OTAs. Around 85% of their bookings come from those platforms. When I put the ad account next to the booking system, the tag was claiming more direct revenue than the booking system actually showed. Measured on direct website sales alone, the spend looked like it barely broke even. Measured against everything the business sold in that period, it looked spectacular.

Neither number is the truth. The honest answer for that account sits somewhere between the two, because the ads were clearly feeding the OTA listings and the tag was clearly counting things it should not.

Blended MER, the number that keeps you honest

The measure I use for this is blended MER. It is one division.

Total sales from your booking system, divided by total ad spend, for the same period. All channels. Direct, OTA, phone, walk-in.

It deliberately ignores what the conversion tag claims. It answers a simpler and more useful question. For every unit of money that went into ads, how much did the whole business sell.

Blended MER is not attribution. It does not tell you which click caused which booking, and it will move with seasonality like everything else in tourism. Used carefully, next to the comparisons below, it is still the closest thing an operator has to the real effect of the spend.

How to see the OTA lift in your own data

You do not need new software for this. You need your OTA dashboards, your booking system export, and your ad account, looking at the same date range.

• Compare OTA sales for the advertised tours before and after the campaigns started. Then do the same for tours you never advertised. If the advertised ones jumped and the others did not, that gap is your lift
• Check the same weeks last year, so a seasonal rise does not get credited to the ads
• Watch what happens when you pause. If OTA sales for those tours sag a few weeks after you switch campaigns off, you have your answer from the other direction
• Track blended MER monthly, next to the tag's own number. The gap between them is your combined tracking loss and OTA lift, and watching it move tells you more than either number alone

Write the numbers down each month in one place. This effect only becomes visible across months, and memory is not a measurement tool.

What this changes about your decisions

Judging tour ads on the tag alone leads to one specific mistake. You cut spend that is working because part of its output lands on a platform the tag cannot see.

To be clear about what this is not. Pushing direct bookings is not about escaping the OTAs, and I never sell it that way. The OTAs are a sales channel you should want to be strong. The point of the direct channel is that you own the customer, you can sell them the second tour, and you are not one policy change away from a bad quarter. The ads feed both sides of that at once.

So the practical rules I run accounts by are these.

• Never kill a campaign on the tag's number alone. Check direct backend sales and OTA movement first
• Judge months on blended MER, and use the tag for what it is good at, which is comparing campaigns against each other
• Treat a strong OTA lift as evidence the ads work, and as a reason to keep building the direct side, not to stop

Common questions

Do Google Ads really increase OTA bookings?

In the accounts I run, the pattern shows up whenever a meaningful share of volume already books through OTAs. Advertised tours climb on the OTA listings in the same weeks the campaigns run, while unadvertised tours sit still. The effect is real. The size of it varies by operator, which is exactly why you measure it in your own data instead of trusting anyone's percentage.

What is a good blended MER for a tour operator?

There is no universal number, because margins, seasonality and channel mix differ too much between operators. What matters is your own trend. Establish your baseline over a few months, then judge changes against it.

Should I stop advertising if most bookings land on OTAs anyway?

No. It means your ads are producing sales the tag cannot show you, which makes them look worse than they are. Measure the blended effect first. Then decide with real numbers, and keep growing the direct side for the ownership, the repeat sales and the independence it brings.

Pull three numbers for last month: total ad spend, direct website sales from your booking system, and OTA sales for the tours you advertise. Put them in one row. That is your starting baseline, and next month you will know more about your ads than the ad account does.