Sa Dec’s bus station is on the far side of the Sa Dec River, a little to the south of town—despite what xe-oms may say, it is walkable at under a kilometre from Sa Dec post office and down town area. Outside of Tet there is no need to book your travel in advance.
If you are heading to Cao Lanh, any bus bound for Long Xuyen or Chau Doc should pass by the southern ferry crossing. Ask to be dropped there, get the ferry across and then either a xe-om or local bus into town. Same goes in reverse. If you are in a hurry (as we were), a xe-om between the two towns should cost around the 80,000 dong mark and will certainly be faster than the local bus!
Sample regional fares include:
Ca Mau: 108,000 dong
Ho Chi Minh City: Departures throughout the day, taking 3 hours and costing 65,000–100,000 dong depending on the operator.
Rach Soi: (for Rach Gia and ferries to Phu Quoc): 48,000 dong
Tra Vinh: 83,000 dong