Traffic has been significantly heavier on Parramatta Road, one of Sydney's most congested roadways, due to motorists using it to avoid the first day of tolls on a widened stretch of Sydney's M4 motorway between Parramatta and Homebush.

After a month-long toll holiday ended on Tuesday, motorists began forking out for the journey as toll gantries on the M4 were activated for the first time since 2010. The distance-based tolls range from $1.77 to $4.56 each way for cars and motorbikes, or $5.30 to $13.67 for trucks and other heavy vehicles.

Travel times in both directions along western parts of Parramatta Road blew out by about 20 per cent on Tuesday. Traffic was also queued for up to 4 kilometres along Woodville Road from where it intersects with Church Street at Parramatta.

Transport for NSW said it was not unexpected to see motorists avoid the M4, which was "normal for the opening of any new toll road".