Did you know that 20% of Americans speak a language other than English in the home? And of these bilingual Americans, the overwhelming majority (62%, or 34.5m, according to the 2007 census) are Spanish-speakers, representing a massive e-commerce consumer market.

Last month, I wrote about how British e-commerce businesses should be taking advantage of targeting non-native English speakers in the UK, especially the Polish community, with specialised foreign  language websites.

There are two major benefits in having translated websites for your non-native English speaking customers in your home country – the first being that people prefer to shop online in their native language, and the second being that you get a better return on your search marketing in languages other than English, due to there being less competition.

This month, I’d like to shift the focus from the UK to the US, where the population that speaks Spanish as its first language wields massive consumer power.

The purchasing power of US Hispanics was measured at $870bn in 2008, a number that exceeds the GDP of Mexico and Canada combined, and the Selig Center for Economic Growth estimates that this will increase to $1.2 trillion in 2011, with $21.6bn being spent online by Hispanics (JupiterResearch).

The US Hispanic community is a rapidly growing online consumer market, representing 11% of the total US online market – research by eMarketer shows that there are 32m Hispanic Americans online this year, a number that is predicted rise to 40m in 2014 – and it’s no secret that Hispanic Americans are the fastest growing demographic in the US. And yet, digital marketing that’s localized for Latino-Americans is relatively rare.

Best Buy famously launched a full online Hispanic marketing campaign with their website almost entirely duplicated in Spanish – with all new content and promotions going straight onto both language versions, the website is efficiently bilingual. And the efforts appear to have paid off – Best Buy reports that users of the Spanish language website spend twice as long browsing and, more importantly, spend twice as much as English-speaking customers per visit.

Home Depot, the home improvement giant, has also committed itself to being a company of choice for Hispanic consumers, but is going after the market in a slightly different way. Their multicultural marketing tactics have included being the official sponsor of a US tour by the Mexican national football (soccer) team, as well as a Spanish language Home Depot YouTube channel with how-to-tips.

Another great example of localized digital marketing within the US is the success of ads on MySpace Latino. A study by eMarketer found that the Spanish ads on MySpace Latino were 15-20% more effective than English ads.

But before you get on the phone to your translation company, there are a few things to keep in mind. Simply translating your website into Spanish doesn’t automatically boost your sales to the Hispanic community.

It’s worth investing some time in researching Hispanic online spending patterns to ensure you’re using the right marketing tactics to reach your new audience. For instance, SIMM surveys conducted a study which found that 54% of Hispanics regularly use Facebook, as opposed to 43% of Caucasians – Hispanics mainly use the web for social networking, shopping and transferring money.

As such, you’d do well to incorporate social media marketing and advertising into your strategy. And, as with translating websites for any foreign language market, it pays to always ensure your keywords are fully localised.

With return on investment (ROI) for localisation estimated at $25 for every dollar spent, it’s undeniably a worthwhile endeavor. But rather than searching abroad for new markets, why not take a look at the multilingual opportunities within your own country, starting with a website en Español for the local US Hispanic market.