During the recent years, bus subsidy in Hanoi has been increasing while a downward trend has been seen for ridership. This leads to a suspect about the effectiveness and efficiency of subsidy. The method of subsidy is based on kilometre. This approach generally is not involved in the financial outcome of public transport, that is, revenue. Therefore, subsidy based on passengers is worth considering. This study analyses factors associated with subsidy for one kilometre and one passenger in order to make comparisons. The advantages of this research are using longitudinal 10-year data of the whole network and deploying ordinal logit modelling. Findings emphasize that impacts of factors on subsidy for one kilometre and one passenger are dissimilar. One passenger-based subsidy shows a more logic in the associations with factors compared with that for one kilometre. However, subsidy based on one passenger needs to be improved by counting correctly passengers travelling by monthly tickets.