| Country: | THA |
| Alternate Name: | Si Rat–Outer Ring Road Expressway ทางพิเศษสายศรีรัช–วงแหวนรอบนอกกรุงเทพมหานคร |
| Maint: | Bangkok Expressway and Metro |
| Length Km: | 16.7 |
| Direction A: | West |
| Direction B: | East |
| Terminus A: | Outer Ring Road (West) (Kanchanaphisek Road) |
| Terminus B: | Si Rat Expressway |
| Prachim Ratthaya Expressway ทางพิเศษประจิมรัถยา | |
| Established: | 22 August 2016 |
The Prachim Ratthaya Expressway, also known as the Si Rat–Outer Ring Road Expressway, is an expressway in Thailand, located in Bangkok and Nonthaburi province. The expressway is a controlled-access toll road.[1]
Prachim Ratthaya Expressway was completed and opened in its entirety on 22 August 2016. It connects Si Rat Expressway to Outer Ring Road (West) (Kanchanaphisek Road). The expressway's name Prachim Ratthaya was bestowed by King Vajiralongkorn, meaning "Road to the West".
According to an official EXAT annual report, the expressway was used by 18,466,598 cars in the 2022 fiscal year, with an average of 50,594 cars per day.[2]
Kilometre 0 is counted at Kanchanaphisek Interchange.
| Prachim Ratthaya Expressway | |||||||
| Location | km | Eastbound | Facility | Westbound | |||
| Exit destinations (road) | Toll Plaza (Entry) | English | Thai | Toll Plaza (Entry) | Exit destinations (road) | ||
| Bangkok | 16.70 | Northbound - Ngam Wong Wan, Chaeng Watthana (Si Rat Expressway) | Bang Sue 1 (from Si Rat) | Si Rat Junction | ต่างระดับศรีรัช | Bang Sue 2(to Si Rat) - exit only | Southbound - Phaya Thai, Phra Ram 9, Si Lom (Si Rat Expressway) |
| Bangkok Bus Terminal, Chatuchak Park (Kamphaeng Phet Road) | - | Kamphaeng Phet 2 | - | ||||
| 12.85 | Wong Sawang (Bangkok-Nonthaburi Road) | Rama VII Bridge | Pracha Rat 1 Interchange | แยกทางด่วนประชาราษฎร์สาย 1 | Rama VII Bridge | Bang Pho (Pracha Rat 1 Road) | |
| 12.62 | Expressway bridge over the Chao Phraya River | ||||||
| 11.95 | Bang Kruai, EGAT (Charansanitwong Road) | Bang Kruai | Charansanitwong Interchange | แยกทางด่วนจรัญสนิทวงศ์ | - | Bang Kruai, EGAT (Charansanitwong Road) | |
| Nonthaburi | 7.40 | - | Bang Bamru | Bang Kruai Interchange | แยกทางด่วนบางกรวย | Bang Phlat | Bang Bamru railway station, Bang Phlat (Sirindhorn Road) |
| Bangkok | 4.17 | - | Taling Chan | Borommaratchachonnani Interchange | แยกทางด่วนบรมราชชนนี | - | Ratchaphruek Road, Suan Phak (Ratchaphruek Road) |
| Borommaratchachonnani | |||||||
| 0.00 | - | Chim Phli | Kanchanaphisek Interchange | แยกกาญจนาภิเษก | - | Taling Chan, Bang Yai (Kanchanaphisek Road) | |