Sipitang Express is a bus operator with a strong presence in East Malaysia. They operate under the same management as Jesselton Express, which also has a significant presence in these parts.
Trips from Kota Kinabalu to Sipitang are just the one to mention. There also trips to Menumbok, which serves as a gateway to Labuan island. They also cross the border to Sarawak and Brunei as well.
Their buses are fully air-conditioned with, reclining seat and more than enough of legroom, all equating to nothing less than a comfortable travel experience. Their trips are all priced at reasonable rates, making it easy on the travel budget.