96-kilometre Bang Yai–Kanchanaburi route available free on weekends, full access expected by October
The Intercity Motorway Route No. 81 (M81), spanning 96 kilometres from Bang Yai to Kanchanaburi, has commenced public trial use as of May 2, 2025. The motorway will be accessible at no charge every Friday from 3pm to Monday at 9am.
During this trial period, only four-wheel private vehicles are permitted to use the motorway, with a speed limit of 80 km/h. The M81 project is slated for full opening by the end of October 2025, at which point it will cover the entire route.