Subway is planning to serve poultry products from turkey and chicken raised without antibiotics.
The move comes after several consumer groups criticized the company for lack of transparency and specific details.
US Public Interest Research Group (PIRG) public health program director Steve Blackledge was quoted by Food Safety News as saying: "Overusing antibiotics on livestock and poultry contributes to a major public health problem, antibiotic-resistant infections. People are increasingly aware of this, and customers have been hungry for meat raised without antibiotics."
At its more than 27,000 fast-food restaurants starting in March, customers of Subway would be able to buy chicken raised without antibiotics, Reuters reported.
In June this year, Subway said that it removed all artificial colours, flavours, and preservatives from sandwiches, salads, soups, and cookies in North America by end of 2017.
Apart from transition to sourcing antibiotic-free turkey and chicken from 2016, the company also plans to phase out serving pork and beef raised with antibiotics by 2025.
Subway's purchasing cooperative executive vice president Dennis Clabby said: "A change like this will take some time, particularly since the supply of beef raised without antibiotics in the U.S. is extremely limited and cattle take significantly longer to raise. But we are working diligently with our suppliers to make it happen."
Subway is a family-owned company which currently serves made-to-order sandwiches and salads at more than 44,000 franchised locations in 111 countries.
Apart from Subway, McDonald's Corp has expressed that it would buy only chicken raised without antibiotics important to human medicine by 2017 for its restaurants in the US, reported Reuters.
