The applicants must be resident in the US, Canada, Australia or UK – or making use of the Schengen Agreement.
In a statement the Royal Oman Police confirmed the rule changes would benefit citizens of: Azerbaijan, Armenia, Albania, Uzbekistan, Iran, Panama, Bhutan, Bosnia, Peru, Belarus, Turkmenistan, The Maldives, Georgia, Honduras, Salvador, Tajikistan, Guatemala, Vietnam, Kyrgyzstan, Kazakhstan, Cuba, Costa Rica, Laos, Mexico and Nicaragua.
The news comes just days after it was announced that people from India, Russia and China were being given the same opportunity.
Those entitled to make use of the new visa rules can also bring their spouses and children under the same arrangement.
While the rules surrounding tourism visas have been eased for people from the 28 nations, anyone traveling to Oman should still hold a passport that is valid for at least six months and a round trip ticket.
And their residency for one of the four countries listed should still be valid at the time of application and travel.
The Omani authorities also recently reduced the minimum wage expats need to earn before they are allowed to move their families over with them.
The announcement comes as the Omani leadership looks to diversify its economy – including revenue generated by tourism under the “Tanfeedh” program.
It is hoped that by making it easier for certain people to get into the Sultanate that they will then spend more money, thus boosting Oman’s economy.