SMS compliance in Thailand

The rules that apply to business SMS sent to numbers in Thailand, with the source for each.

Quiet hours

Marketing SMS recommended 08:00-20:00.

Source: NBTC consumer protection / operator practice

Consent

Prior consent required for direct marketing under PDPA.

Source: Personal Data Protection Act 2019

Opt-out

Promotional SMS must offer a free, simple opt-out (e.g., reply STOP); honour requests promptly and suppress opted-out numbers.

Source: Operator/aggregator policy (best practice)

Prohibited content

Blocked: phishing/fraud, illegal or unlicensed gambling, adult content, hate/political content (most operators), counterfeit/illegal goods, unlicensed financial offers; URL shorteners often blocked.

Source: Operator content policies / national advertising law

Data protection law

Personal Data Protection Act 2019. Supervisory authority: PDPC.

Source: Personal Data Protection Act 2019

Sender ID rule

Alphanumeric SID (max 11 chars) supported; pre-registration required on some or all networks; generic SIDs (INFO, SMS, ALERT) blocked. See SenderID sheet.

Source: Operator rules (see SenderID sheet)

Other

Classify traffic as promotional or transactional; OTP/transactional must not contain marketing content; use local language or Unicode where required.

Source: Industry practice

This summary is guidance, not legal advice. Last verified 23 October 2026.