The closest airport is in Mae Sot, serviced from Bangkok by daily flights with Nok Air. The bus station is within walking distance to the west of the airport, making it easy to transfer to an Umphang-bound songthaew without too much fuss.
Hourly dark-blue songthaews depart for Umphang from the Mae Sot bus terminal from 07:00 to 14:00 for 130 baht per person. The trip takes four to six hours, depending on how long the driver cruises around town picking up passengers and stacking the roof with watermelon and cucumbers.
The songthaews can get packed and motion sickness should be expected along twisting Highway 1090. There’s one bathroom break around the halfway point. Drivers can drop off passengers directly at their accommodation of choice; otherwise they’ll let you out in the centre of town on Prawatprawin Road or next to the hospital.
From Umphang, hourly songthaews depart for Mae Sot from 06:30 to 12:30 from in front of the hospital on Ratpattana Road. They can also be flagged down along Prawatprawin Road, or you can arrange for your resort to call for a pick up.
Hourly songthaews to Poeng Kloeng also pick up in front of the hospital from 06:30 to 15:30 for 100 baht.
Umphang is a great town for wandering around on foot, with lots of attractive old wooden houses and several eateries clustered in a relatively small area around Prawatprawin and Sukkumwattana roads. Surprisingly we didn’t come across bicycle rental, but Umphang House rents out at least one automatic motorbike for 250 baht per day.