Stable prices in Japan coupled with a weaker yen against major currencies also accounted for why Hong Kong overtook Tokyo this year as the most expensive city in Asia.
"This means that for many companies, the cost of maintaining their assignees' purchasing power while posted here has fallen and international assignees based in Japan may see their cost of living allowances decrease," Quane said in the release.
ECA gathered the results by collecting price data across 464 cities, comparing a pre-determined basket of goods and services that are commonly purchased by expatriates globally.
This basket includes groceries, meals, leisure activities and expenditure on clothing and general services. It excludes certain expenses such as rent, utilities, automobile purchases and tuition fees that are usually provided by companies when their employees relocate overseas.
Most of the cities featured in ECA's top 25 most expensive locations in Asia Pacific this year are concentrated in East Asia — with Seoul as the third expensive city, Shanghai as the fourth and Macau at the 11th position.
More Chinese cities were added in this year's survey to reflect the growing presence of multinational companies in the country, Quane told CNBC.
City-state Singapore, which rivals Hong Kong as a financial hub, came in at the 10th position for the Asia-Pacific region, and even fell by 6 places globally to the 24th most expensive city in the world. Although the Lion City often tops cost of living rankings, Quane told CNBC that his methodology differed from other surveys.
Angola's capital, Luanda, topped this year's list as the most expensive city in the world. Weak infrastructure capabilities and high oil-fueled demand coupled pushed the Southern African city to the top of the list. It's a regular at the top of cost of living lists.
Currency fluctuations from the weaker pound, as a result of last year's Brexit vote, pushed Central London out of ECA's top 100 most expensive cities to 132, making it cheaper for expatriates to live in as compared to Paris, Bangkok and Rio de Janeiro.
The bi-annual cost of living survey is conducted by ECA to measure how much is required for companies to set overseas living allowances for employers to ensure that employees are able to maintain a similar standard of living while working abroad.