TOTSO is a term for a special form of road junction.
TOTSO is an acronym which stands for Turn Off To Stay On. It is used to describe junctions where a motorist has to turn off the current physical road, to stay on a particular road number. If the main through road is followed through the junction, one will join a seperate route.
TOTSOs exist in principle in many cities, where a street name does not follow the through road. However, the term is used mainly for highways because the phenomenon is not the expected behaviour for major routes, and can be confusing for motorists unfamiliar with the junction.
- On the A4, at the Heumar triangle junction in Cologne, motorists from the west must turn off to continue on the A4.
- At the junction of the A5 and A67 is a striking example where motorists on both roads from all directions must TOTSO.
- On the M6 motorway, motorists heading south must turn off to remain on the M6, as the through road becomes the M6 Toll
- On the M25 motorway at junction 5 near Sevenoaks, a motorist continuing around the M25 in either direction must TOTSO, as the anticlockwise carriageway continues as the M26 to the east and the clockwise carriageway as the A21.
- On the M42 motorway near Birmingham, motorists heading from the M5 must TOTSO as the through road becomes the M40. Further north, motorists must TOTSO again as the through road becomes the M6 Toll.
- The A159 near Scunthorpe features two TOTSOs in quick succession.
- The A205 south circular in London is not a purpose-built route, but a collection of pre-existing suburban roads joined together. As a result there are frequent TOTSOs.
- The A271 in East Sussex features a TOTSO, where the through road changes to the A269 road
- At the East Los Angeles Interchange, a number of TOTSOs exist: Northbound on the I-5, as the route changes from following the Santa Ana Freeway to the Golden State Freeway; Westbound on the I-10, as the through road heads to U.S. Route 101; Westbound on SR 60 as the through road heads to the I-10. The Santa Ana Freeway is the only road that crosses the complex without a TOTSO.