Red River Delta: 9 provinces
(Bac Ninh, Ha Nam, Hai Duong, Hanoi, Haiphong, Hung Yen, Nam Dinh, Ninh Binh, and Thai Binh);
North East: 12 provinces
(Bac Kan, Cao Bang, Ha Giuang, Lao Cai, Lang Son, Tuyen Quang, Thai Nguyen, Phu Tho, Vinh Phuc, Bac Giang, Quang Ninh, and Yen Bai);
North West: 4 provinces
(Dien Bien, Hoa Binh, Lai Chau, and Son La);
North Central Coast: 6 provinces
(Ha Tinh, Nghe An, Quang Binh, Quang Tri, Thanh Hoa, and Thua Thien–Hue);
South Central Coast: 6 provinces
(Binh Dinh, Da Nang, Khanh Hoa, Quang Nam, Quang Ngai, and Phu Yen);
Central Highlands: 5 provinces
(Dak Lak, Dak Nong, Gia Lai, Kontum, and Lam Dong);
Southeast: 7 provinces
(Baria–Vung Tau, Binh Duong, Binh Phuoc, Binh Thuan, Dong Nai, Ho Chi Minh City, and Ninh Thuan);
Mekong River Delta: 12 provinces
(An Giang, Bac Lieu, Ca Mau, Can Tho Dong Thap, Hau Giang, Kien Giang, Long An, Soc Trang, Tien Giang, Tra Vinh, Vinh Long).