Currency and billing: the settings that quietly kill trust at checkout
Your Google Ads account currency is locked in the moment you create the account and it cannot be changed afterwards. If you set up your account in GBP years ago, every budget, every CPC bid, every report you pull will show in pounds, even when you're pointing campaigns at shoppers in Paris or Berlin who are converting in euros. That's not a dealbreaker, but it does make comparing performance across markets harder than it should be, because you're mentally converting currencies every time you look at a report.
Where this actually causes damage is in Google Merchant Center. Your product feed for each target country needs to use that country's local currency exactly, EUR for France, EUR for Germany, and so on. Submit a French feed priced in GBP and Google won't just show the wrong price, it will disapprove the products outright. That's a common reason a Shopping campaign that worked fine in the UK simply produces zero impressions in a new country, and it gets missed because the error sits in Merchant Center, not in the ads themselves.
The same logic applies on your actual site. A shopper in Spain who lands on a product page still showing £45 will hesitate, do the mental conversion, wonder if there's a hidden card fee coming, and quite often just leave. Mentioning the price in euros in your ad copy doesn't fix this if the site itself still shows pounds. Prices need to convert properly on-site, not just in the marketing around it.
Billing and VAT invoicing can also need separate handling per country depending on your structure, and this is genuinely worth a conversation with your accountant before you scale spend rather than after. For comparing campaign performance fairly across currencies, use Google Ads' built-in currency conversion in reporting rather than eyeballing raw numbers side by side, it does the maths properly for you.
On the site side, this is a solved problem. Shopify and WooCommerce both have established multi-currency plugins built specifically to handle local pricing, and they should be configured and tested before the ads go live, not scrambled together after the first week of confused-looking conversion data.
Translating your site is not the same as localising it
Translation swaps words for words. Localisation changes the imagery, the sizing conventions, the colour associations, the tone, and the trust signals so the site feels like it was built for that market, not bolted onto an English one. These are genuinely different jobs, and doing only the first while assuming you've done the second is one of the most common expensive mistakes UK sellers make when they expand.
The evidence on this is pretty consistent: merchants who properly localise convert better than those who simply translate the copy, because shoppers pick up on trust signals almost unconsciously. An address format that looks foreign, a payment logo they don't recognise, a size chart that clearly wasn't written for them, all of these quietly raise doubt even if the shopper can read every word perfectly well.
Getting the language itself right matters too, and not just at the level of vocabulary. Missing an accent or a piece of punctuation in translated copy can genuinely change what a word means, turning a perfectly professional line into something unintentionally embarrassing. This is exactly the kind of error a native speaker catches instantly and a quick machine translation won't.
Sizing is the other one that trips up UK sellers constantly. UK shoe size 8 is EU size 42, and clothing sizing follows a different scale entirely across most of Europe. If you're selling anything wearable and you haven't built a size guide or an automatic conversion tool into the product page, you're asking every European shopper to guess, and guessing is exactly what makes people abandon a cart.
Checkout forms need the same attention. A UK-style address form with a house number, street, town, and postcode field doesn't map cleanly onto address formats, phone number formats, or postal code structures used elsewhere in Europe. A German or Dutch shopper hitting a form that clearly wasn't built for their address style will notice within seconds, and it's an unnecessary friction point right at the moment they're about to hand over their card details.
For anything beyond a short-term test, it's worth investing in a native-speaking copywriter to produce permanent localised pages rather than leaning on browser auto-translate indefinitely. Auto-translate can get you through a pilot, but proper localised pages also let you implement hreflang correctly, which supports organic visibility in that market too, something a browser plugin can never do for you.
VAT, customs and the compliance settings that can stop sales dead
The EU's One Stop Shop scheme lets UK sellers register once and report VAT across EU consumer sales through a single return, rather than registering separately in every member state you sell into. The detail that catches people out is timing: OSS registration needs to happen before your first EU sale, not once you notice orders coming in and scramble to sort it retroactively.
Since Brexit, UK sellers no longer get the benefit of the old EU distance-selling thresholds that used to give small sellers some breathing room. VAT is now generally due from the very first sale to an EU consumer, and this genuinely surprises a lot of small businesses who assumed they could test a market quietly before dealing with the paperwork.
Customs duties and import VAT get charged in one of two ways: Delivered Duty Paid, where you as the seller cover it upfront and the price the customer sees is the final price, or Delivered At Place, where the customer gets charged extra on delivery. If your checkout doesn't make it completely clear which one applies, you end up with parcels refused at the door and returns clogging up your logistics, and that whole cycle also poisons your customer reviews and repeat purchase rate in that market.
There's a Google-specific compliance point too. Since March 2024, Google has required Consent Mode v2 on any site collecting conversion and remarketing data from visitors in the EEA. Without it properly implemented, your ad measurement for EU campaigns degrades, and so does the accuracy of Smart Bidding, because the algorithm is working with gaps in the data rather than a full picture.
Before switching on Shopping or Search ads for EU traffic, get an accountant involved on VAT and OSS registration, and update your checkout terms and conditions per country so shoppers know exactly what they're agreeing to and who's responsible for what.
None of this is just a legal box-ticking exercise. Ignoring compliance doesn't only risk fines, it directly damages ad performance, because refused deliveries, confused checkouts, and unhappy customers feed straight back into lower conversion rates, and lower conversion rates feed into a weaker Quality Score for the exact campaigns you're trying to grow.
