To & from Tan Son Nhat Airport: you can take a metered taxi, a minibus or a bus: Taxi drivers must wear an official name badge and turn on the meter. Taxi stands are in both domestic & international terminals at the left end of the buildings. Beware of unregistered taxis at the Ben Tanh Market in downtown!   It takes about 40 minutes to get from the Airport to Ho Chi Minh's District 1.
Hotels can arrange for guest transport, which should be reserved in advance. 
Rental cars are not available at the Airport.  However, Budget offers rental car with English-speaking driver - tel. +84 8 3939 1118.

Buses at Domestic Trminal stop a Column 18; at International Terminal at Column 15

The most economical way is by Bus 152 (color white & blue) takes on average 30 mins into the City. This bus can make stops at hotels situated along De Tham and Dong Khoi streets (Ben Thanh Market - Trung Son residential area)  Note that bus fare and luggage are charged separately - both fees are identical.
New 'high-end' Bus Roue 109 to city center opened in April 2016, which runs from 5:45am-1:30am (after midnight) every 15-20 minutes - taking 45 minutes into town. The bus stops at Column 15 of the International terminal and at Column 18 at the Domestic Terminal. Its route is as follows:  Truong Son – Tran Quoc Hoan – roundabout of Lang Cha Ca – Hoang Van Thu – Nguyen van Troi – Nam Ky Khoi Nghia – Nguyen Dinh Chieu  - Cach Mang Thang Tam – Pham Hong Thai – Le Lai – roundabout of Ben Thanh – Ben Thanh Station – Pham Ngu Lao –Park 23/9.
Bus 49 runs between the Airport and Ben Thanh Market until 2am in the morning.

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