Up to the current day, my search for a traditional Thai massage in Phimai hasn’t yielded many results. One quite large massage facility can be found at the Phimai Elderly Society.
If this facility is run by the elderly or caters to them is not quite clear but seen as some of the massage therapist are older, I would bet on the first option. The service is clearly geared towards local clients and should be judged that way. The building is not maintained very well, but isn’t dirty and should be seen as an outdoor location. No elaborate interior (or any at all, for that matter), no uniforms for the employees, no English language skills, just basic good massage at a more than reasonable price (130 baht/hour for traditional Thai massage, more prices underneath). Before the massage you need to change in (cleanly washed) massage attire (linen shirt and fisherman’s pants), like at most places. The massage was very good and the therapist was clearly very experienced at her trade. Stars are lost due to the slightly too inquisitive nature of the therapist and too much chatter between her and colleagues/customers. I would still recommend it and will return. The place is relatively hard to find. On my next visit I will ask about the address, and I will add it to the Phimai Tourist map I am planning to make.