TL;DR:You must have a visa/work permit or an authorised remote‑work visa to freelance legally; taxes, social security, professional licences, company setup and banking rules also apply.
Freelancing in Thailand is legal only when your immigration and work-permit status authorises paid work. Key constraints: you cannot perform paid freelance work on a tourist/visa‑exempt/VOA stay; most foreign freelancers need either a work permit tied to a Thai company or one of the formal routes that allow remote work (e.g., Destination Thailand Visa/DTV, SMART or specific long‑stay visas where permitted). Employers/sponsors and work permits define permitted job categories and duties. Tax and social‑security obligations apply once you earn income in Thailand: register with the Revenue Department, file personal/company tax, and enroll for social security if employed locally. Small business rules (VAT registration thresholds, bookkeeping) and professional licensing (health, legal, engineering, etc.) may also restrict certain freelance activities. Banking and invoicing: Thai bank accounts may require proper visa/residence documents and a Thai taxpayer ID to receive client funds easily. Check Thai Immigration, the Department of Employment/Ministry of Labour, and the Revenue Department for current rules and specific visa eligibility.
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