According to the latest update of the Henley Passport Index, prepared by the consulting firm Henley & Partners in collaboration with the International Air Transport Association (IATA), the Portuguese passport allows visa-free access to 188 destinations, a ranking that, for the second consecutive year, is topped by Singapore, whose passport allows visa-free access to 193 destinations.

In second place are the passports of Japan and South Korea, which allow visa-free visits to 190 destinations. This is followed by a series of European countries, which make up the majority of this ranking, with 28 European countries appearing in the Top 10.

Denmark, Finland, France, Germany, Ireland, Italy, and Spain share third place, as their passports allow visits to 189 destinations, one more country than the Portuguese passport. Austria, Belgium, Luxembourg, the Netherlands, Norway, and Sweden also share third place, which allows visits to 188 countries.

Greece, Switzerland, and New Zealand round out the top five, with passports allowing visits to a total of 187 countries without a visa, while the United Kingdom ranks sixth, allowing visits to 186 countries.

In total, the Top 10 most valuable passports in the world include 28 European countries, justified by their access to the Schengen Area and strong diplomatic relations. Although there are also exceptions, such as Belarus, which ranks 62nd on this list, with access to 81 countries, the lowest position held by a European country.

The latest update of the Henley Passport Index also reveals that the US passport is losing value. The country held the top spot in this ranking in 2014 and is currently ranked 10th, with access to 182 destinations, the lowest position the US has held since this list was compiled, approximately 20 years ago. More restrictive entry policies in recent years are cited as the reason for the US's drop on this list.

In contrast, countries such as the United Arab Emirates, which moved to 8th place, Saudi Arabia (54th) and China (60th) are rising in the rankings, due to the latest visa waiver agreements and easing of entry requirements.