Operated by SBST
| Direction | First bus (wkday) | Last bus | AM peak | AM off-peak | PM peak | PM off-peak |
|---|---|---|---|---|---|---|
| Blk 403 → Orchard Stn/Lucky Plaza | 07:25 | 08:02 | 12–13 min | — | — | — |
| Orchard Stn/Lucky Plaza → Blk 139 | 18:18 | 18:42 | — | — | 12 min | — |
First/last bus are at the origin stop, weekdays. Frequencies are LTA's scheduled ranges in minutes.