We decided to reverse our itinerary after having read about the many troublesome stories of border crossings from Thailand to Cambodia. From Manila we flew (3 hours) directly to Siem Reap, stayed a few wonderful days to see the temples, then did a land crossing to Bangkok. Luckily our Cambodia to Thailand experience was hassle free!
Our hotel arranged for a private taxi costing USD$35 to bring us from Siem Reap to the Poipet border. Drivers on standby could give it for USD$30 but for peace of mind we used a reputable cab arranged by our hotel. It was a two hour drive through the very rural outskirts of Cambodia. Along the highway you get a glimpse of simple Cambodian provincial life; hogs and chickens transported via motorbikes, children biking to school, monks walking and a scenery of endless rice fields. The roads are in good condition but there are no fast food chains or modern gasoline stations for stops.
The Poipet border immigration counter looked like the ticket booth of a bus station. It is about a 10 minute walk to the Thai border but surprisingly in-between this stateless stretch were several casinos!! Really odd to find such dingy places but they became useful for a toilet stop, we pretended to be guests for a free shuttle to the border.
If you need to obtain a visa, best to get an e-visa online. ASEAN member countries do not
need to get a visa. Border horror stories are from the long queues and rip offs coming into Cambodia from Thailand. In our case, the immigration lines to get into Thailand were much shorter. The whole process took us only 45 minutes.
We were able to bargain for a private taxi for 1700 Baht or haggle between USD$50-65. It took us another 4 hours from Aranyaprathet to Bangkok. The only glitch we encountered was being stuck in the Bangkok city traffic for an additonal 2 hours finding our hotel and that our driver did not speak any English.
There is no straight connection from Siem Reap to Bangkok, this is when the scam usually happens. I recommend the best way is to take a Cambodian taxi from Siem Reap to the Popeit border, then another Thai taxi from the border to Bangkok. It is safer, faster and more comfortable. A bit more costly but you can always split the fare and share with other travelers.
If you need a guide in Cambodia, Mr. Chhom Samithy is educated, trustworthy and has worked for the United Nations. His email firstname.lastname@example.org , +855 12893181