Do I need to register upon entering Thailand on a non-immigrant O visa as a guardian?

Upon entering Thailand on a non-immigrant O visa as a guardian, registration is not mandatory in Bangkok. There is no need to file the TM.30 form as the local immigration office does not require it. However, if you are staying at a private residence, you may need to ask your landlord to complete the registration within 24 hours after arrival using the TM.30 form. If the landlord is unwilling, you can collect necessary documents to register yourself.