Living or working in Kanchanaburi you can extend your Thai visa at Thai Immigration in Kanchanaburi. You can extend your visa at their office such as a marriage visa or a retirement visa. You can also ask them about customs duties for your goods coming into Thailand.
If you already have an extended visa then you will need a re-entry permit to leave Thailand without invalidating your visa when you return. You can also apply for a visa transfer from one passport to another at Thai immigration.
Thai Immigration in Kanchanaburi
100/22 Mae Klong road
Amphoe Muang
Kanchanaburi 71000
Tel: 0-3456-4279
Email: c_kan@immigration.go.th / d3_kanchanaburi@immigration.go.th
