More and more Americans are retiring outside of the United States, and those numbers are only expected to increase in the next 10 years, according to figures from the country's social security administration office.

The number of Americans choosing to live overseas when they retire increased by 17% from 2010 to 2015. That's nearly 400,000 American retirees living in places such as Canada, Japan, Mexico, Germany and the United Kingdom - some of the most popular retirement locales.

These Americans cite the cost of living as one of the principal reasons for making such a huge change in their lifestyle. They can live better and cheaper abroad; for example, they may be able to afford to pay for someone to clean, cook and do their laundry.

According to the Pension Research Council at the University of Pennsylvania's Wharton School, American pensioners also see moving to another continent as an opportunity to see other countries while they are still well enough to do so.

‘I think that many people retire when they are in good health and they are interested in stretching their dollars and seeing the world,’ said Olivia Mitchell, director of the Pension Research Council.

However, depending on where they choose to spend their retirement, many find that one of the main problems can be language. According to Viviana Rojas, an associate professor at the University of Texas at San Antonio, understanding the culture can also create problems.

Rojas is undertaking a study of Americans who have relocated to Mexico in retirement. Of those she has interviewed, she's found that while many claimed to be able to speak Spanish, in reality they spoke very little of the language.

‘They didn't have the capacity of speaking enough Spanish to meet their basic needs like going to the doctor or to the store,’ Rojas explained. She says that speaking a language while on holiday, for example, is not the same as when you actually live in a country and have to deal with everyday matters such as health, tax, finance, utilities and banking.

Indeed, Mitchell cites Pension Research Council studies showing that access to health care can be a challenge while living abroad, and retired people are more likely to need it than those on holiday.

Depending on the country they have moved to, they may also have to pay for their healthcare - which may be more expensive than in the US. However, in some countries it is cheaper.