EF's English Proficiency Index (EPI) is an annual global survey which this year involved 950,000 adults across 72 non-Anglophone countries.
In its 2016 edition, Switzerland ranked 14th in the world for non-native English proficiency, five places higher than in 2015 and the first time in five years that its ranking has risen.
With a score of 60.17 out of a possible 100, the Swiss were judged to have a ‘high' level of English proficiency, better than four years ago when it was judged ‘moderate'.
Switzerland beat European countries including France, Spain and Italy, whose English language skills fell in the ‘moderate' category.
It also leapfrogged Romania, which ranked ahead of Switzerland last year.
However multilingual Switzerland still lags behind Europe's top non-native English speakers, including the Netherlands, which topped the survey with a ‘very high' level of English proficiency.
People in Denmark, Sweden, Norway, Finland, Singapore and Luxembourg were also considered to have a ‘very high' level of English.
As last year, neighbours Austria (8th) and Germany (9th) also beat Switzerland on English language skills.
Women were better English speakers than men across almost all nations and age groups, found the study.
Within Switzerland English proficiency varied between regions, with people in Zurich judged to have the best English skills and those in French-speaking regions being the least proficient.
Among the country's main cities, people in Lausanne were found to be the least proficient in English.
This variation is reflected in Switzerland's ongoing row over what languages should be taught in schools.
A 2004 federal education strategy specifies that two languages should be taught in Swiss primary schools, at least one of which should be a national language.
But citing lack of resources and time, some cantons in German-speaking Switzerland want to teach just one language, and say that should be English.
Their stance caused an outcry, with the government saying in July that the Swiss constitution decrees the “safeguarding and promotion of national languages”.
However, French-speaking cantons generally toe the line and prioritize German, followed by English.