The United States was tied for 19th with Malaysia, Ireland and Canada among 193 member countries of the United Nations and six internationally recognized territories, according to Arton Capital, which compiles the rankings.
Passport Index notes that "While Singapore quietly climbed the ranks, the U.S. passport has fallen down since Trump took office".
The Canadian passport didn't do as well as previous year, but it was still ranked one of the most powerful in the world in a global survey.
"It is a testament of Singapore's inclusive diplomatic relations and effective foreign policy".
A Singaporean passport holder can now show up in 159 different countries, receive a stamp upon arrival, and stay legally in the country for 30 days without any application process.
In recent months, Singapore and Germany have been tied for first place, but Singapore rose to the number-one spot after Paraguay recently removed visa requirements, Arton Capital said on October 25.
The Passport Index's Global Passport Power Rank 2017 has ranked India at a lowly 75position. Georgian citizens can enter 67 countries visa-free and 38 upon arrival (total 105 countries).
Travelers can view the full list of powerful passports here.
Arton Capital's Passport Index, updated in real time, is one of several indexes created by financial firms to rank global passports according to the access they provide to their citizens. China is ranked 67 with a visa-free score of 60.
The Nomad Passport Index, meanwhile, ranks 199 citizenships on five factors: visa-free travel, global taxation, perception, dual citizenship and personal freedom. Although in the "individual classification", the Belarussian passport is listed as coming in at 109th place, and Oman 111th place.
Germany and Sweden ranked second and third, with a score of 158 and 157, respectively in the index.