But employers must still provide reasonable accommodation for those exempt from mandatory immunization under the Americans with Disabilities Act and Title VII of the Civil Rights Act.
Employee incentives are also permitted to encourage more Americans to get shots in their arms as the percentage of vaccine doses continues to reduce nationwide.
Employers are prohibited from issuing "coercive" incentives, but guidelines on what could be construed as illegal were not included.
"A very large incentive could make employees feel pressured to disclose protected medical information," the EEOC said, though the agency did not expand on what would be considered a disproportionate incentive.
Just over 50 percent of the U.S. population have received at least one dose of the coronavirus, with over 167 million Americans partially vaccinated.
Despite broad access, just 40 percent of Americans are fully vaccinated with over 134 million having received the full vaccination.
President Biden pledged to have enough vaccines for every American by the end of July, but a drastic drop of shots administered could jeopardize that target.
The U.S. saw peak rates of vaccinations in early April with over 4.3 million doses administered on April 1, according to data by the Centers for Disease Control and Prevention (CDC).
But by May 28, less than 130,000 doses were administered.
The coronavirus has infected over 33 million people nationwide and 170 million globally.
Nearly 591,000 have died in the U.S., along with 3.5 million worldwide from the virus.