As a general rule, form 15 CA and form 15 CB are must-have documents for a repatriation process. While Form 15CA is mandatory in case of all remittances, Form 15CB is mandatory for remittances greater than Rs. 5 lakhs. There are certain types of remittances as mentioned in rule 37BB of Income Tax Act which is liable to tax in which case no information is required to be furnished in the forms.