The process has already begun with S&P Dow Jones (SPDJI) and FTSE Russell adding major Saudi stocks from the Taduwal index to its global indices on 18 March.
Starting with a 50% weighting, SPDJI's exposure will rise to 100% in September, meaning it will have make up 3% of the S&P Emerging BMI, while the country will have a 2.9% weighting in the FTSE Emerging All Cap index.
Meanwhile, MSCI, who revealed plans to include the country in its major indices last June, is including the Taduwal into major indices in a two-step process that will see Saudi stocks become 2.7% of its MSCI Emerging Markets index.
This will make Saudi Arabia the eighth-largest country in the flagship index, which tracks around $1.9trn in assets.
As a result, analysts estimate inflows into the kingdom from passive funds could be around $20bn, with foreign investment jumping from around 2% to 6%, according to Reuters.
For example, the US-listed iShares Core MSCI Emerging Markets ETF has $59bn assets under management (AUM). Following the 2.7% increase, this will lead to inflows of $1.6bn into Saudi Arabia from that one product alone.
ETF issuers this side of the pond are yet to grab the opportunity. Invesco is the only ETF provider to offer direct Saudi exposure through its $341m MSCI Saudi Arabia UCITS ETF (MSAU), which launched last June.
PerformanceIn response to the positive sentiment, the Tadawul All Share index is trading at its highest level in nearly four years and is up 11.3% this year.
Along with the impact on Saudi Arabian stocks, investors tracking emerging market indices will also need to reconsider their exposure.
The inclusions come at a time when Saudi is under increasing scrutiny following the murder of journalist Jamal Khashoggi last year.
Despite this, Saudi finance minister Mohammed al-Jadaan insisted last December the kingdom remains "attractive for investment", adding "growth opportunities for investors are high and investors will find many of them".
Edward Evans, portfolio manager at Ashmore Group, commented: "Saudi Arabia offers significant investment opportunities, including considerable low hanging fruit.
"Crown Prince Mohammed bin Salman's 2030 Vision for the development of Saudi Arabia's economy centres around diversifying the country's income sources beyond energy. As part of these efforts the Kingdom is opening up to overseas investors."