Portsmouth is an English Unitary Authority.
| Year | All Motor Vehicles | Cars and Taxis | Road Network Total Length |
|---|---|---|---|
| 2000 | 742,700,000 | 622,800,000 | 276.1 miles (444.3 km) |
| 2001 | 745,600,000 | 623,500,000 | 276.8 miles (445.4 km) |
| 2002 | 760,900,000 | 637,500,000 | 277.4 miles (446.5 km) |
| 2003 | 760,700,000 | 628,700,000 | 278.1 miles (447.6 km) |
| 2004 | 769,200,000 | 633,600,000 | 278.7 miles (448.5 km) |
| 2005 | 751,500,000 | 619,000,000 | 279.0 miles (449.0 km) |
| 2006 | 752,900,000 | 621,500,000 | 281.3 miles (452.7 km) |
| 2007 | 741,500,000 | 609,600,000 | 282.5 miles (454.7 km) |
| 2008 | 713,500,000 | 585,000,000 | 281.5 miles (453.1 km) |
| 2009 | 715,200,000 | 589,600,000 | 280.4 miles (451.3 km) |
| 2010 | 717,200,000 | 587,400,000 | 282.0 miles (453.8 km) |
| 2011 | 721,700,000 | 592,000,000 | 281.4 miles (452.8 km) |
| 2012 | 734,100,000 | 600,100,000 | 282.2 miles (454.2 km) |
| 2013 | 729,200,000 | 593,800,000 | 282.5 miles (454.7 km) |
| 2014 | 733,900,000 | 596,200,000 | 282.6 miles (454.8 km) |
| 2015 | 750,300,000 | 607,200,000 | 283.4 miles (456.1 km) |
| 2016 | 760,500,000 | 612,500,000 | 283.8 miles (456.8 km) |
| 2017 | 763,100,000 | 615,100,000 | 284.0 miles (457.1 km) |
| 2018 | 748,800,000 | 603,100,000 | 285.9 miles (460.1 km) |
| 2019 | 758,400,000 | 611,700,000 | 285.8 miles (460.0 km) |
| 2020 | 589,600,000 | 460,700,000 | 285.1 miles (458.9 km) |
| 2021 | 671,000,000 | 525,700,000 | 285.2 miles (458.9 km) |
| 2022 | 757,000,000 | 596,500,000 | 284.0 miles (457.0 km) |
| 2023 | 755,800,000 | 602,100,000 | 284.1 miles (457.2 km) |