The number of people not paying their road tax has topped two million.
According to figures released by the Department for Transport, an estimated 2,193,000 drivers failed to pay their vehicle excise duty last year, up from 1,549,000 in 2005.
The report showed non-payment was costing a small fortune, with £217m in lost revenue in 2006/07, compared with £147m in 2005/06.
But, 80% of that is expected to be recovered through subsequent improvement, a DfT spokesman said.
In recent years the Driver and Vehicle Licensing Agency has run a high-profile TV advertising campaign telling people to pay their road tax on time or face certain prosecution.
Evasion rates are highest for motorcycles and "other" vehicles, the figures show. In addition, evasion among cars and vans that are more than 10 years old is five times as high than those which are less than a decade old.
The report revealed there were 1,338,000 unlicensed cars and vans on the road in 2006, costing an estimated £170 million in lost revenue.
The average value of a licence for these vehicles is £127.
The largest increase in non-payment was in the North West, the DfT revealed. The statistics in the report are based on checks conducted at 256 sites across the United Kingdom. In total, around 1.3 million registration marks were collected, and checked against computer records.
The data were collected before new measures were introduced by the DVLA in June last year to tackle the problem. The measures included debt collectors to target owners who ignore penalty notices and doubling wheel clamping operations.
