FREE FARES have a way of drawing riders to a bus route, but there are other ways to attract passengers as well.

In a presentation to the MBTA board last week, General Manager Steve Poftak said two of the transit authority’s 25 busiest routes are now exceeding their pre-COVID ridership levels. Two others are getting close. By contrast, the three routes that are part of a city of Boston fare-free pilot are doing well but not back to pre-COVID ridership levels yet.

Poftak compared ridership on April 18 this year to April 15, 2019. The biggest rebound was on the Route 16 bus, which runs from Forest Hills in Jamaica Plain through Franklin Park, up Columbia Road to South Bay, and ending at Andrew Station on the Red Line. Its ridership was at 116 percent of its pre-COVID level, the highest in the system.

The other big gainer was the Silver Line 3 bus, which runs from Chelsea to Logan International Airport in East Boston and from there to the Seaport and eventually South Station. Its ridership level was at 109 percent of pre-COVID levels.

Two other bus routes are also performing extremely well. The 117 bus, running from Maverick Station in East Boston to Chelsea, Revere, and ending at Wonderland on the Blue Line, was at 98 percent of its pre-COVID ridership. The 104 bus, running from Sullivan Square through Everett to Malden Center, was at 93 percent of its pre-COVID level.

The three buses currently operating with no fares are some of the busiest on the system, but they are not back to pre-COVID levels yet. All three routes operate in Roxbury and Dorchester and connect riders to four subway stations at Ruggles, Jackson Square, Mattapan, and Ashmont. 

The Route 28 bus was the highest of the three, serving 89 percent of its pre-COVID ridership. The Route 23 bus was at 84 percent and the Route 29 bus was at 67 percent.

MBTA spokesman Joe Pesaturo said ridership on the Route 16 bus has increased because capacity has expanded to meet the demand. He said the number of daily weekday trips of the Route 16 bus has grown from 122 in the fall of 2019 to 184 in spring 2021, an increase of 51 percent. 

Pesaturo said the resurgence of the Silver Line 3 bus is harder to explain. Half of the route is in Chelsea, but the rest covers well-served stops between Logan and South Station via the Seaport area. 

Poftak indicated the bus routes returning the fastest to normalcy are those where riders don’t have the option of working from home and have relatively few travel options. Conversely, the routes growing the slowest serve riders who have more options on work and travel.  

The Route 73 bus, which operates between Harvard Station in Cambridge and Belmont, was at only 39 percent of its pre-COVID ridership. The Route 31 bus, which runs between Forest Hills and Mattapan, was at 45 percent.