Guernsey and Jersey in the Channel Islands have independent tax rules from the UK and require some special processing in a Magento eCommerce website – here is how to go about it.

First of all lets look at the sales tax rules in these three jurisdictions. UK sales tax or VAT (value added tax) is currently charged at 20% and needs to be applied to all orders payed for/delivered to the UK. Jersey has a similar system called GST (goods and services tax) that is currently 5%. Guernsey on the other hand doesn’t have any sales tax at all.

The place you need to be looking to configure all of this is in the main menu under Sales->VAT. Once you have set-up the customer and VAT classes, or used the defaults you need to add your tax rates and regions in the Manage Tax Zones & Rates. Here you specify a country, optionally post/zip codes and rates. So for our situation you would expect the configuration below.

Guernsey doesn’t need to be there at all because there is no sales tax.

The above set-up works except for one very major problem. Many people in both Guernsey and Jersey will enter Guernsey/Jersey as a Country, or different line of the address and select United Kingdom from the country list. This is because Guernsey and Jersey residents are used to websites excluding them as separate countries (which they are!) and lumping them in the the UK. Also, some credit card providers need to see UK in the address in order to validate the payment – even though it is technically incorrect. Either way we need to work a little bit harder to make this work.

We can’t assume people will enter Guernsey/Jersey in the country box as some people are likely to enter Channel Islands there and Guernsey or Jersey in the field above. The best field to rely on is the postcode.

Fortunately both Guernsey and Jersey have their own postcode prefix which we can use to exclude them from paying UK VAT even when the UK is selected. Guernsey is prefixed GY and Jersey JE. Unfortunately however Magento does not allow us to exclude just these postcodes, so we must include all of the other postcode prefixes (or just all letter combinations which is easier).

IMPORTANT UPDATE: It turns out Glasgow uses G as a prefix to it’s postcodes immediately followed by a number, so the below rules will ommitt VAT thinking the postcode is in Guernsey. As well as the exceptions for each letter (other than y) you will need to add an exception for each number e.g. G0, G1, G2. Thanks to Tom Robertshaw for spotting this.

Please feel free to use this on your own site – I live in Guernsey so it will save me some money ;-)