The Energy Regulatory Commission approved a new progressive residential tariff effective with September 2026 bills. The average charge for all user types falls from 3.95 to 3.86 baht per unit (excluding VAT). The first 200 units are capped at 3 baht per unit, and the 201-400 and 401+ tiers drop by about 6 satang. The change applies only to households, not to business tariffs. It also extends the household definition to residents without a permanent house registration who have at least 6 months of payment history. Owners of small shops or home businesses on residential meters should check whether their meter size and tariff category are affected.