For a SIM problem, contact the mobile operator. For an accommodation-reporting issue, ask the accommodation owner or manager first and contact Phuket Immigration if formal advice is needed. For entry-status questions, rely on Immigration rather than a hotel, mobile shop or social-media post. Keeping the three systems separate makes the paperwork much easier to understand.
If details change or something was missed
Arrival and immigration procedures attract unofficial websites that charge service fees for forms that can be completed through government systems. Start with Thailand Immigration's official TDAC and TM30 services, and use your mobile operator's official channel for SIM verification. Be cautious about uploading a passport scan to an unknown intermediary.
Use official websites, not lookalike forms
Save your TDAC confirmation, keep a clear copy of the passport identity page and current entry/permission stamp, and retain any TM30 or 90-day-report evidence relevant to a longer stay. A screenshot backed up to cloud storage is useful, but carry the original passport when Thai authorities or your specific transaction requires it.
Keep your immigration records organised
Foreigners permitted to remain in Thailand for more than 90 days have a separate residence-reporting obligation commonly called the 90-day report or TM47. Immigration describes this as the foreign national's own recurring duty; it is not the same as the landlord's TM30 and it does not extend a visa or permission to stay.
TM30 is not 90-day reporting
If you stay in a private home, villa or condo, do not assume the requirement disappears. The official system specifically supports owners, landlords and accommodation businesses. For longer stays or when you will later deal with Immigration, it is sensible to confirm that the owner or responsible person has filed the notification and can provide evidence if needed.
Private villas, condos and informal rentals
At a properly run hotel or guesthouse, staff normally collect passport details at check-in and handle the accommodation notification as part of their back-office process. That is why being asked to show or briefly hand over your passport at reception is normal. You generally do not submit the hotel's TM30 yourself.
What happens at a normal hotel
TM30 is different again. Under section 38 of Thailand's Immigration Act, the house owner, head of household, landlord or hotel manager accommodating a foreign national must notify immigration of that person's residence. The official TM30 system states that notification is required within 24 hours of the foreign guest's arrival at the accommodation.
TM30 is the accommodation report
The official system asks for passport details, travel and arrival information, an address in Thailand, purpose of travel, health-declaration information and an email address. It is an arrival-information form, not a visa and not an extension of permission to stay.
What the TDAC asks for
For current arrivals, do not rely on old advice about keeping a paper departure card. Thailand now uses the Thailand Digital Arrival Card (TDAC). The Immigration Bureau says non-Thai nationals entering Thailand must submit their arrival information before arrival, with the form available within the official pre-arrival window.
TDAC replaced the old arrival-card routine
An eSIM changes the delivery method, not the identity rules. If you buy a Thai operator's tourist eSIM, follow that operator's passport-verification process. International roaming eSIMs sold by overseas providers can work differently because they may not be a Thai mobile number at all; read the plan description rather than assuming every “Thailand eSIM” is the same product.
eSIM does not mean anonymous SIM
Thai mobile operators require SIM users to be registered. Foreign visitors should expect to show a passport when buying or activating a physical tourist SIM. AIS, for example, tells foreign users to have their passport, SIM and phone ready when completing identity verification. Buy from an operator shop or authorised seller if you want the cleanest registration trail.
Tourist SIMs must be identity-registered
There are three different “registration” topics travellers often mix together in Thailand: registering a local SIM to a real identity, submitting the Thailand Digital Arrival Card before entry, and the TM30 accommodation notification made after a foreign guest checks in. They are separate systems with different responsibilities.