The Fare Review Mechanism Committee assured public transport commuters on Monday that it would look closely into segments of users who fall between the cracks.
These include average-income households where measures such as a monthly adult pass to cap monthly expenses are being looked into.
Committee chairman Richard Magnus, a former senior district judge, wrote in a blogpost on Monday that these average-income earners "would not show up as a possible group that might need help", going by statistics.
He added that they may spend 3 to 4 percent of their household income on transport fares and as such should find them quite affordable.
He said: "However, the reality is that this is not a homogenous group as there are some heavy public transport users."
Other groups the committee will look into include low-income earners, the disabled community, and polytechnic students.
The Fare Review Mechanism Committee was tasked last June to relook how fares for public bus and train services are set and are likely to reveal their findings by end of May.
The existing fare formula takes into account three factors: operators' productivity, inflation and national average wages.