It is 335 metres (1,099 ft) long, running adjacent the Royal Albert Bridge, and part of the A38, a main road between the two counties.

During the 20th century, there was increasing demand to replace or supplement the Saltash and Torpoint ferries, which could not cope with the rise in motor traffic.

A reconstruction of the bridge began in 1999 after it was found to be unable to support a European Union requirement for goods vehicle weights.

It has become a significant landmark in Plymouth, Saltash and the surrounding area, and used on several occasions for protests or to highlight the work of charities and fundraisers.

The north of these is used as a local access route from Saltash, while the south is used by cyclists and pedestrians but could be converted to meet future vehicle demand if alternatives for pedestrians and bicycles were provided, a dedicated ferry, shuttle bus, cable car or bridge have been considered.

An electronic device called the Tamar Tag can be affixed to a vehicle window, which allows the driver to travel at half-fare.

[21] Invitations to tender were sent on 4 March 1959, and a proposal from the northeast England-based Cleveland Bridge & Engineering Company was accepted on 9 June.

The bridge was built using suspended construction, which involved building two 67 metres (220 ft) concrete towers with support cables over these.

They were constructed for Cleveland Bridge and Engineering by British Ropes Ltd.[6] The deck was made out of a concrete base covered with 20-millimetre (0.79 in) steel plates approx and 200-millimetre (7.9 in) of standard road tarmac.

[29] The eventual solution was to add two additional orthotropic cantilever lanes either side of the bridge, which traffic could run on while the original road deck was replaced.

Reconstruction started in 1999, and was slightly delayed owing to an influx of tourists travelling to Cornwall to watch the solar eclipse of 11 August 1999, whose line of totality passed through the county.

[19] Work was completed in December 2001 at a total cost of £34 million; the two additional lanes were retained to increase the bridge's capacity.

[3] The Tamar Bridge was officially reopened by Princess Anne on 26 April 2002, exactly forty years after the initial opening.

[30] Traffic was not expected to increase following the expansion of the bridge, as the Saltash Tunnel further west acts as a buffer for capacity.

He visited the bridge shortly after its reconstruction, and hoped that such methods could be possibly used to expand capacity on the three lane Mid-Hudson Bridge across the Hudson River in upstate New York[32] In April 2022, a campaign pressure group known as the Tamar Toll Action Group was formed.

[33] In 2023, the Tamar Bridge Committee announced a hike in prices due to its losses upwards of £2 million per year.

[35] In March 1998, after the closure of Europe's last tin mine at South Crofty in Cornwall (which later reopened for a period, and subsequently closed), the Cornish Solidarity Action Group (CSAG) encouraged commuters to pay the then-£1 toll in pennies.