Indonesia has the largest financial technology (FinTech) industry in Southeast Asia: 167 FinTech companies offer payment, lending, personal finance, crypto and blockchain, crowdfunding, Insurtech and point-of-sale (POS) services. Two entities regulate the FinTech industry: Bank Indonesia and Otoritas Jasa Keuangan (OJK). The Indonesian FinTech ecosystem encompasses savings and investments, money transfer and payments, POS, lending and borrowing, accounting, comparison, financial planning, crowdfunding and cryptocurrency. Money transfer and payments take up the highest percentage, currently at 50%, in all FinTech ecosystems with the most digitally active customers. Peer-to-peer lending dominates the Indonesian market. The FinTech subsectors offer financial management, crowdfunding and insurance services. The abuse of this technology in facilitating terrorist financing, the weaknesses of the laws and policies, and the need for reform and remedies are discussed.