Time to Zap the ZIP

Graham Rhind

The internet abounds with question and answer forums. I followed an interesting discussion recently on a Nigerian forum where a user asked what the Nigerian ZIP code was, as he needed to complete an online form. The vast majority of answers insisted that the answer was 234 (that’s Nigeria’s international telephone country code), but if that wasn’t working on the online form, add the city’s number, for example 23401.

One lone voice


The lone voice that tried to explain that ZIP code is synonymous with the (hardly used 6-digit) Nigerian postal code was drowned out by the 234-strong crowd.

This is not a rare problem, and the ideas put forward to get people through the forms are very worthy… but are hardly conducive to collecting good data:


Divided by a common language

Why should Nigerian users know what a ZIP code is? Zone Improvement Program, or “ZIP” codes, were created by the United States Postal Service (USPS) and it’s a term that’s only widely used and universally understood in the United States.

The United Kingdom has postcodes. India has PIN (Postal Index Number) codes. Many other countries use the more generic term “postal codes”.

This is not just an English-language issue, and it applies to other parts of addresses too. A post office box in France is a Boîte Postale… but step over the border into Switzerland and you would empty your Case Postale. Canada uses the latter terminology too. Spaniards have an Apartado de Correos, while many Latin American countries have an Apartado Postal – and still others have a Casilla de Correo!

Administrative challenges

Whereas you’d probably be asked your state in the USA, you’d need to ask for a province or territory in Canada, a state or union territory in India, a state or territory in Australia, a canton in Switzerland, a department in France or a county in Romania.

It’s also a challenge to get one’s head around the administrative situation in some other countries, such as the UK!


This ZIP won’t work on the fly

When you’re collecting data via an online form, translating the form into the local language increases response rates and improves the quality of the data collected. But translation is not enough – the terms used and the fields presented need to be localised into the version used in that country.

Online forms in English for the USA, the UK, Ireland, India and Australia would all look very different, using different fields and different terms which local customers would understand.

Doing little to aid data quality

The fact is this: if forms are in a single language, such as English, the use of local terms such as “ZIP code” will reduce response and increase data pollution.

Field labels need to use generic terms (such as postal code) and not be afraid to explain what is required. Short, pithy field labels may be the ideal for many user experience professionals but they do little to aid data quality!

Even if you do want a short field name, there’s nothing to stop you applying a mouse-over explanation. A label Postal code/Postcode/ZIP code/PIN code may not look very flash, but it will mean more to most people than ZIP.

About The Author

Graham Rhind

Graham Rhind is an acknowledged expert in the field of data quality. He runs his own consultancy company, GRC Database Information, based in The Netherlands, where he researches postal code and addressing systems, collates international data, runs a busy postal link website and writes data management software. Graham speaks regularly on the subject and is the author of four books on the topic of international data management. You can find him on Twitter via @grahamrhind.

Practical International Data Management Online.  A free resource from GRC Data Intelligence. For comments, questions or feedback: pidm@grcdi.nl